Here's an example of the kinds of unique programs we can expect on the upcoming Android platform: WiFi Army, a game that takes place in the real world using GPS and your phone's camera. Basically, when you get in range of other players your phone will let you know and show you who your enemy is. You then take them out with "weapons" and "ammo" that I assume come up when you point the camera at them.
It sounds sort of fun but also sort of awkward, as I can't really imagine running around aiming my phone at some stranger on a crowded street. It would also be really annoying to get attacked while you were out on a date or something, having to explain that it was just some guy who was engaging you in your phone's virtual first person shooter. In any case, there's a beta open for this, although with no Android phones out yet I'm not sure how you can participate in it. [Product Page via Ubergizmo]