Currently I'm playing Thief: The Dark Project, and it scares the crap out of me (like most first-person-style games tend to do)! But hey, I'm halfway through it so I must not be too terrible at it!
...Though once I get tired of constant heart attacks I take a break with Animal Crossing: City Folk, where I don't have to worry about getting accosted by guards or having my face torn off by a zombie.