Although simple to play, Bejeweled 3 is a fun game that one can put many hours into without even realizing. It has many different modes, including my favorite, Zen mode which is basically Endless mode. I love this game so much I have variations of it on multiple devices (Console, iOS, etc). I can't recommend this game highly enough.

Borderlands is an amazing co-op experience. I can't tell you how much fun I had driving around with 3 other people and just doing quests. The controls are top notch. The game is a bit short, but it can be played again on a harder difficulty (with better loot!). For me, it's all about opening those beautiful containers and getting the next best sniper rifle.

I highly recommend Audiosurf especially if you have a large collection of music. It's interesting and has several modes of play. I enjoy Ninja Mono (a simple collect and avoid game).