All objects are free
Hit L and R together on the main menu to bring up the cheat menu. Then type in FREEALL.

All two player games,locked items, and skins
Hit L and R together on the main menu to bring up the cheat menu. Then type in MIDAS.

To get a First-Person View
Press L + R on the Title Screen and then type ''FISH EYES''.

Unlock 'Party Motel' two-player game
Hold L + R at the main menu to bring up the cheat menu, then type PARTY M.

Unlock 'Play the Sims' mode at any time
Hold L + R at the main menu to bring up the cheat menu, then type SIMS.