Here's an interesting video on UAVs. It shows some of
the work being done at NASA and has a short segment
on the iPhone as an airborne camera:

http://www.pbs.org/kcet/wiredscience/video/163-diy_uavs.html

FYI, I work in the next building to these guys - they're
always flying their stuff around us and threatening to
cut people's heads off....

You can get started on this hobby for $25 at Fry's.

Alex