Little Big Planet is very addictive. It was obviously meant for younger folk but it's challenging enough and quirky enough that adults will enjoy it. It actually requires a partner in some sections so it's a great way to break your significant other into gaming. "Honey, I need help, can you come and run this second cute little rag doll guy around for a minute? I put bunny ears on him, just for you."
InFamous was my other choice based on a friends high recommendations but I have yet to try it. Left it to download last night.
