I couldn't live without Angry Birds HD
Also if like me you like to watch movies when travelling on a plane etc. AVPlayerHD is a must. You don't have to rip movies to mp4, it reads avi's no problem
If you didn't already know it I'll tell you, at 100% battery I watched a 2½ hour movie on a flight and still had 87% battery left
It's the best device I've ever owned, and nothing can beat it for surfing the web