The Sims 3 PC Game Cheats

Cheat codes:

During gameplay, press CTRL+SHIFT+C (CTRL+SHIFT+WindowsKey+C for Vista) to bring up the cheats menu. Enter the listed code to activate the corresponding cheat function.

Confirmed cheats:

constrainFloorElevation [true/false] - Force terrain adjustments regardless of objects, Sims, and other structures
enableLlamas - Enables llamas
jokePlease - Summon a joke
hideHeadlineEffects [on/off] - Hide all meters and effects
quit - Quit the game
help - Lists all available commands
slowMotionViz [x] - Slow motion, where [x] is 0-8 (0 is normal)
resetSim [x] - Resets the named Sim with neutral motives, no moodlets, and teleports Sim back home where [x] is first and last name
fps [on/off] - Toggles frames per second in upper right of HUD
fadeObjects [on/off] - Toggles object fade when camera zooms
testingcheatsenabled - Turns on Testing Cheats, for Sims (Shift click) and objects
disableSnappingToSlotsOnAlt [on/off] - Hold Alt to avoid object snap when toggled
kaching - While on the lot, this gives you $1,000
motherlode - While on the lot, this gives you $50,000
moveobjects on/off - Move anything (including Sims) in your Buy/Build mode
familyFunds [x][y] - Give money to a family, where [x] is the family's last name and [y] is the amount
fullscreen [on/off] - Toggles windowed mode
unlockOutfits [on/off] - Unlocks outfits in CAS (Create a Sim) mode. Note: Must be enabled before entering CAS

Unconfirmed cheats:

force service sim [x] - A specific service Sim will show up, where [x] is a name
Add to Household - Add the active Sim to the current household
Modify Traits - Bring up Trait Modification window
Make Me Know Everyone - Everyone in your town becomes an acquaintance
make happy - Gives household perfect moods
make motives [static/dynamic] - Makes motives static or dynamic for whole Household
make friends for me - Selected Sim knows everyone in town
Set Age [x] - Set the age of selected Sim, where age is [x]
Edit in CAS - Edit the selected Sim in Create-A-Sim
freerealestate - Turn off house costs
napObjectsToAngle [true/false] - Toggles 45 degree angle object snap
snapObjectsToGrid [true/false] - Toggles snap to grid for placed objects
Force Event - Click on a Career Building for a random career event
Force All Events - Click on a Career Building to display all events for the career consecutively
Force Opportunity - Click on a Career Building to force an opportunity
force visitor - Summon a visitor
set career [x] - Give the selected Sim a career, where [x] is the career
Set Career [x] - Give the selected Sim any career at any level where [x] is the career / level
shazaam - Gives 2,500 Lifetime Happiness Points to active Sim

Testing cheats:
Hold CTRL+SHIFT+C (CTRL+SHIFT+WindowsKey+C for Vista) and enter "testingcheatsenabled true".

Then, hold SHIFT and click your letterbox to display the following options:

-Make All Happy
-Force Visitor
-Set Career
-Set level

Or, hold SHIFT and click on Sims to display these options:

-Add Sim to House
-Change Sim Traits
-Force Aging

In Ground View mode, hold SHIFT and click a spot and your Sim will teleport to it.

Cooking skill exploit:
This glitch requires a TV with a cooking channel and a video game system. First, have one Sim sit down and watch TV. Switch the TV over to the cooking channel so that the Sim can start earning its skill point. Now, have a second Sim go over and start playing video games. You should now notice that although the TV is displaying video games, the first Sim still has the skill meter above its head! Simply allow this Sim to sit there until it decides to go do another activity on its own. After that, the skill meter should stay above its head until you start another cooking skill activity. As an added bonus, you can train two skill points at once! i.e., Go work out and both the athletic and cooking skills will continue to rise.

EA games easter egg:
When your Sims take a video game break, you can zoom in on the TV and identify various EA games on the tiny screen.