I am sure there are some really creative or silly uses for the iPad out there that nobody thought about. How about a thread gathering these?
I start:
http://www.maya.com/sprocket
For the iPad owning cyclist.
"For the launch of the iPad we thought we’d create a simple app that could be worn by a cyclist as a display mounted on their back. The app just does a few basic things. If you are going to stop or slow down you can trigger a “stopping” sign before you stop. If you are going to be turning in a 100 yards, you can trigger a turn signal that will blink until you complete your turn."