What is the most fun, entertaining, and maybe most useful application for the iPod Touch/iPhone?

Please tell me, as I am going to download some new apps.
Try and keep the under £2 please.

Im assuming the app store would be the best and most usefull...
My favorite is kind of complicated. It requires an additional device / tool. The application doesn't take up a lot of space at all, though. The tool (I can't remember what it's called) is basically an elongated solid metal chassis, with significant mass, set crosswise on an insulated handle. The goal of the app is to apply the tool to the iPhone with an increasing amount of force, measured in Gs. So far my high score is 5671 Gs, but my friend said he got twice as much (I'm skeptical). Everyone should use this application for sure.
iPodGuy7 years ago
I love the one that helps you brew beer.