Okay, each Transformer user can pick FIVE and ONLY FIVE apps to recommend here. Edit your original posts (instead of posting a reply) if you change your mind or move something out of the slot. I recommend apps that are especially suited to the hardware. You don't have to list Wiimote Controller; we'll assume that one is a given.
Here are my current five top apps: (in no particular order)
1. Reckless Getaway
4. MX Video Player