Sims 1: Getting $100,000
Want to build a fancy, schmancy mansion, but can't afford it after buying your lot? Well, with this cheat, you can do so, and MORE! Load up the family you want to give kwik kash to, and then press Ctrl + Shift + C (it might be S, but I don't exactly remember). Type in Rosebud, and you'll have $1,000. Now, that's not much, but here's the second step. Open up the Cheat box once more, but instead of Rosebud, type !;. Don't press enter yet. Keep putting !; into the cheat box until you can't fit any more characters (to make this easier, do !; around 5 times, then simply copy/paste it until it won't let you type any more). Press enter. You should now have around $100,000. Go build the Taj Mahal for your sims.

Sims 2: Getting $50,000
Sick of your sims being unable to build a large pool? Well, worry no more. Simply open the cheat box by pressing Ctrl + Shift + C, and type in Motherlode. You will now have $50,000. Go buy that expensive fountain for your courtyard.

Morrowind: Restoring your health/magicka/fatigue, and GODMODING!!!

Restore Health (Xbox): Are you sick of dying all the time? Well, don't worry. With this cheat, you will restore your health AND keep it that way until you look into the menu screens again. To restore health, go into the menu screen and highlight the Health bar. Now, press black, white, black, black, black, and then A, and your health will fill up to full. To keep it constantly full, press B while holding down black to exit the screen. (NOTE: You can still die if you're hit for more damage than you can take, or if you fall off a high-enough cliff to warrant killing you.)

Restore Magicka (Xbox): Want to cast a BigAss Fireball spell, but have to continually charge your magicka? Can't afford to keep quaffing down those Restore Magicka potions? With this cheat, you'll save a ton of money and time. Simply go into the menu screen and highlight Magicka bar. Now, press Black, white, white, black, white, and then A, and your magicka will fill. To keep it constantly full, press B while holding down white to exit the screen. (NOTE: For high cost spells, you may need to wait a few seconds for your magicka to restore after the cast).

Restore Fatigue (Xbox): Tired of missing when you're battling. Are you getting the crud punched out of you? Well, forget those days! With this cheat, you'll never be knocked down again! Go into the menu screen and highlight the Fatigue bar. Now, press Black, white, white, black, and then press A, and your fatigue will rise. To keep it continuously full, press B while holding black to exit the screen.

Godmoding (PC only): To Godmode yourself, therefore making the game very easy, simply open the command console with the ~ button. Then, type in TGM. Godmode should be on now, and you're free to explore Vvardenfell without worry of dying. Do note, however, that it will be impossible to raise Unarmored, Light Armor, Medium Armor, and Heavy Armor unless you use a Trainer, or turn Godmode off, because if the enemies can't hurt you, your armor will not get any use.

Yu-Gi-Oh: Destiny Board Traveler: Unlocking Suguroku, Kaibaman, Bakura, and Yami

Suguroku: To unlock, press L, right + B, right, B, R, left, down, and A at the title screen.

Kaibaman: Press down, B, left, right, right, R, up + R, and A at the title screen.

Bakura: Press L, down, right, left + B, R, down, down, and A at the title screen.

Yami: Press R, left, B, right, up + R, right, down and A at the title screen.

Yu-Gi-Oh: Eternal Duelist's Soul: Making the duels go faster
When Direct Attack flashes, press B to make it go 3x faster than normal. Also works during opponent's entire turn.

Final Fantasy VI: Easy Stat Raising
To raise a character's usually unraisable stats (like Vigor, Stamina, ect), or to augment raisable ones (like MP, HP), go into the Espers status screen, and look at the bottom of each Esper description. Sometimes, they will have "Level Up" bonuses such as HP + 10% at level up, or MP +30%. Equip these on your characters, and then level up. Within a few levels, you will notice dramatic rises of HP, MP, and the like, and your characters will do much better in battles as a result. Good Espers to use are: Fenrir (MP+30%), Terrato (HP+30%), Bismarck (Vigor +2), Alexandr (Stamina +2), and Bahamut (HP +50%). There are many others, so experiment for yourself and see which works best for you.

Pokemon: How to breed certain pokemon/finding Crescellia and Mesprit.

Azurill: To get an Azurill, if you can't catch one in the wild, you will need two Marills. Breed them with the female holding a Sea Incense. The incense is found in Mt. Pyre for Sapphire.

Wynaut: To get a Wynaut, you will need two Wobbufets. Breed them with the female holding a Lax Incense. The incense is found in Mt. Pyre for Sapphire.

Budew: To get a Budew, you will need two Roselia. Breed them with the female holding the Rose Incense. Though, you'll probably be better off simply catching a Budew, as they aren't rare.

Happiny: To get Happiny, simply talk to the man near one of the Hearthome City gates. He will ask you to care for an egg. Hatch it, and it will be a baby Happiny. Make sure you have one slot empty in your party to receive the egg.

Riolu: To get Riolu, help Riley out in Iron Mountain. When you make it through, he will hand you an egg. Hatch it, and it will be a Riolu. Make sure you have an empty slot in your party, or you'll need to leave the mountain and go back through it to get your egg. Crescellia: To FIND Crescellia easily when it's in the same area as you, put a pokemon under level 50 in your party (make sure it's stronger than the pokemon normally inhabiting the area), and use a Repel. Then, go through the grass, and with any luck, you will run into Crescellia relatively quickly. To prevent it from running, make sure Wobbufet is your starter pokemon, or have an extremely fast pokemon use Mean Look on the first turn. Or, use a master ball if you have it. Make sure Crescellia is in the same area as you before attempting.

Mesprit: See above. Latios/Latias: See above. Suicune/Raicou/Entei: See above, but instead, you will not be able to use Wobbufet in Gold/Silver, as abilities weren't around back then. You will need to either rely on a Masterball (not recommended), or using Mean Look/putting them to sleep, OR by slowly wittling down their HP as they continue to flee.

Radiata Stories: Getting 8,888 Dagols
Go to the Goblin Cemetery at night. There should be a Gold turtle running around (it's quite small, so if you have trouble seeing it, keep searching the area and kicking any small rocks you see). Defeat it, and you'll have 8,888 Dagols.

Harvest Moon: More Friends of Mineral Town: $50,000 easily
Ever get a piece of mail saying you won some win, but have no idea what to use it for? Don't throw it away. Save it, and befriend the wandering salesman, Won. Once you can sell things to him, take the wine, and sell it to him. He'll give you $50,000 for EACH bottle, and you'll probably have 2 or 3 by the time you befriend him. Won is found in Zack's shack near the ocean.

Rune Factory: Beating Raffelsia easily/Improving Cooking with no effort

Raffelsia: To beat the boss in Clemens Cave easily, simply run up to it and whack it until it's dead. Ignore its attacks and the bees it summons. If you're on a high-enough level (I was around 38 and won with 19 HP left at the end, though I had no Rune Points when I began to fight it), you should survive. It helps to have a full RP bar.

Imrpoving Cooking: To do this without wasting ingrediants, make sure you have a kitchen, first off. Next, use the No-Utensil option (it's the shelf-like bar in front of the kitchen). Select any ingredients as long as it's not in the recipe book and that if it is, you can't make it with good accuracy. Press OK, and it'll say Experiment Failed. However, you will still get EXP. in cooking, and your ingredients won't be wasted. This works best with weeds, as they're virtually useless anyway. If you do this with the other utensils, you will most likely get Flop, which can be sold for 10G, but wastes your ingredients. You will still get EXP for flop, though.

Final Fantasy: Mystic Quest: Beat the final boss in two blows
The evil king looks pretty damn scary, doesn't he? Well, he's actually a big baby if you know his weakness. That is... LIFE MAGIC! He's undead. So, if you want to hurt him badly without using Flare or Meteor, simply cast Life on him. That'll shave off around 17,000 HP. Repeat on the next turn. Congratulations, you've just killed a big-ass spider.

Final Fantasy VII: How to avoid Cait Sith's GAME OVER slot
Is Cait Sith really unlucky and continuously giving you the dreaded Joker Doom slot attack? Well, here's how to avoid it... hopefully. If he manages to get it, there are a few things you can try. One, if your timing is good, and you ordered other characters to attack before even attempting Cait Sith's limit, they may get lucky and kill the enemies before you have to accept Cait Sith's roll (you need to press A after he rolls to accept, so you do have some time to think). Another thing is to simply run away. This isn't always effective, but it's worked 90% of the time for me. The third thing to try is to skip his turn. I've never done this, so I can't confirm if that's allowed. The fourth thing is to just not use his Slot limit break.

How to get weak, sick, otherwise useless characters
Are you tired of being a good guy? Have you had it with leveling up? Did your mother scold you for not cleaning your room, and you need something to take your divine fury out on? Well, with this cheat, it's possible! And humorous, too. Now, when you get into battle, the first thing you should do is poison your characters. No, I'm not stupid. With most RPGs (Final Fantasy being the most prevelant), when characters are poisoned, their attack and defense drops over time. Watch in pure amazement as your characters slowly windle down their attacks to doing less than 10 HP of damage. Another alternative is casting ATK down, but that's not nearly as fun as slowly watching them die, is it?
Games this works for: Final Fantasy series, Rune Factory (must have enemy poison you)

Killing enemies... the FUN way!
Are you kicking ass and sick of it? Tired of fighting off puny monsters while you do a quest for a villager? Well, with this, there's no worry. You'll virtually torment your enemies with this horrible trick. First off, when you get into a battle, poison your target. Then, have another character confuse them. Finally, if you're able to, turn said target into a Zombie and cast Regen on them. Because healing magic works in reverse for undead, the target will now have two types of poisons killing it! Now, if you truly want, cast Haste to speed up the process, or Stop so the enemies can't do a thing as the poisons slowly kill them off. Now, watch in sheer confusion as they die of poison. And, if you're truly an evil person, you can use this to give yourself an instant game over!
Games this works for: Most RPGs, but it depends on the spell listings.

Stealing stuff, and not getting blamed for it!
Are you walking through a city, and you see a nice vase you like? Afraid to pick it up because the guards are RIGHT there? Well, I have options for you! In order to steal anything and everything you want, without getting caught, you have two ultimatums. One, you can try sneaking to get it, and if you do get caught, simply open the menu screen and drop it (or everything you currently own if you REALLY get caught). You have about two seconds to do this, or the guards will take everything away, even if you do drop the item you stole. The next is to cast Chameleon (100% mind you) to make yourself blend into the surroundings. You'll rarely get caught with this, so Chameleon is much more reliable for theft. Happy Thieving!
Games this works for: Morrowind

Killing NPCs without getting caught
Are you tired of people calling you a n'wit? Do you want that big manor on the hill, but people are still living there? Well, with this, you can evict them and not worry about being arrested for harrassment OR murder! First of all, you'll need to go stealth mode (Chameleon is STRONGLY recommended here!), and you'll need to quietly make your way behind the NPC you wish to murder. If they turn around, simply try again. If there's a symbol of a noose near your health bar, you'll be unseen as you commit your acts. Now, SAVE YOUR GAME! This is vital if you're about to do something illegal, because if you screw up, you screw up big with NPC murder. Now, get out your weapon, and make sure you're sneaking as you attack. With luck, you'll score a critical hit and down the NPC in one blow. If not, then you just messed up, and you'll need to either restart your game, or run like hell from the ensuing guards/villagers who will be kicking your sorry butt. Also note that some NPCs will always notice your movements no matter how stealthy you are.
Games this works for: Morrowind

Setting Santa on Fire

Your sim is an evil little wench who doesn't believe in Santa Claus. That's cool, but how can you make it so she can eradicate the jolly spirit from time itself? Well, the first thing to do is get a Christmas Tree, a Fireplace, and a plate of Cookies from the Buy mode. Next, put them all in one room, hopefully the living room. Next, turn the fireplace on. Now watch as Santa comes down and... well, you get the rest. Not recommended if kids are watching you play.
Games this works for: The Sims 1

Yu-Gi-Oh: Forbidden Memories: Getting 1,000,000 Starchips
DO NOT BE FOOLED BY THIS TRICK! It will NEVER work. The guy who posted this said that if you want unlimited starchips, kick your PS1 around for a while. He says it's guaranteed to work, but the alternative is that if it doesn't, you have a busted machine. Definitely not worth the risk.

Pokemon Gold/Silver

Getting Hogia: Not even worth the risk. You must breed Lugia and Ho-Oh, and then get to Blackthorn City and back WITHOUT getting into ONE battle. At all. And, you must press A on every step, nor are you allowed to surf or use REPELS. Needless to say, this cheat is a fake. First off, neither Lugia nor Ho-Oh can breed. Second, there is NO WAY you're avoiding all battles while trying this, because encounter rates are terrible in caves (over 75%). Thirdly, all you need to do is look on any pokedex and see that "Hogia" isn't even listed as an actual pokemon. Do not try this, and if you already have, you've wasted a lot of time.

99 Masterballs: Someone posted saying that the first time you're on the S.S. Aqua, look in any garbage bin and you'll find 99 masterballs. Is a fake. Tried it, it doesn't appear to work.

Final Fantasy VII: Getting Sephiroth in your party
An online guide once said to defeat Jenova the first time on the boat (heading the Costa Del Sol for the first time). Then head out of the room you fought her in and go back in. Sephiroth is SAID to be there, and that if you talk to him, he will join you. He NEVER appeared in my game. There may be other ways to hack him into your party, but this cheat is a complete fake.