So whattaya get when you combine an iPhone, a Twitter client, and a classic kid's game?
"hideNtweet" is the answer — and another example of the phrase "augmented reality" that's been bandied about recently. To play, take a picture of yourself, then one of "home base." If you're playing solo, the game will introduce the four "ghosts" seen above as your opposition. Track them down and tag them out (i.e. snap their picture) before they can get to home base.
The real fun comes when you get real, live opponents that you can hunt (utilizing your 3GS's GPS functionality) or hide from. Plus — as you might have guessed from the name — hideNtweet is a full Twitter client that lets you read and post tweets while playing, and posts your in-game pictures to yfrog.com.
If nothing else, hideNtweet may be the only iPhone game in which you HAVE to get off your ass to play…