Wild Planet SpyCams
The SpyCam takes 20 640x480 pictures. While this might not be enough pictures to fully document a project, the camera itself is ripe for hacking. It's super small and light and only requires a single AAA battery. I can imagine loading it on a model rocket, plane, or something else that flies. When connected to a computer, it can take continuous images. With some code and some patience, you could probably connect this to an Ipod or other storage device and make a video camera light enough to be carried by kite or candle powered hot air balloon.
All except the first two images were taken by the SpyCam.