CamBox is an iPhone app by Billaboop which allows you to create beatbox clips using iPhone’s built in video camera. Each sound you make triggers the recording of a short video sequence, which is stored into a box. You can then play the boxes with the touch screen and save it as a video. The jams can then be shared on Facebook, YouTube, Twitter and more.
More information at http://www.creativeapplications.net/iphone/cambox-iphone-sound/