FingerBeat for iPhone

From FingerBeat:

FingerBeat for iPhone is a virtual instrument designed for creativity and self-expression. A homage to Dance Music & Pop Culture from the last decades. A classic for absolutely everyone. Streamlined to be intuitive and immediate, FingerBeat aims to be a pick-up-and-play tool to quickly annotate musical ideas, create beats and above all, have fun doing it. Grab your own sounds using the iPhone microphone or use it to sing over your creations. Is this party boring? Just plug it in the stereo and be the Master of Ceremonies. Your creations are automatically saved on exit and recalled when you load the application for total immediacy, so you can just pick it up where you left off after that five minute subway ride.