"These aerial images of White Sands National Monument [top] and Glen Canyon Dam [left] were taken by a Canon SD30 carried on a radio-controlled model airplane [right], using CHDK to operate the shutter."
IEEE Spectrum magazine on the great CHDK software, which allows you to control Canon cameras remotely. The whole piece is long and interesting, so read it all, but here's a bit about what CHDK is:
"The CHDK firmware resides on the camera's memory card, but the original Canon firmware remains on the camera's internal flash memory. So you're not likely to "brick" your camera by using CHDK inappropriately. Indeed, you can return your camera to its stock configuration merely by restarting it without CHDK on its memory card or by switching the locking tab on the card to its unlocked position. (CHDK loads only if the card is locked, and once this firmware is loaded, the camera can still record images.) The CHDK firmware is described fully on the wiki athttp://www.chdk.wikia.com, which includes a "CHDK for Dummies" section and plenty of pointers for getting up and running."