From Makezine, a good use of a RaspberryPi board to capture and stream video from a balloon:
PublicLaboratory is a fantastic citizen scientist organization with really useful projects like DIY spectrometers (for finding out what’s really in stuff) and aerial mapping for monitoring of oil spills, landfills, etc. They’ve done some fantastic work using the continuous shooting mode of consumer cameras, including converting them to near infrared. The problem is that there is little or no control over the camera and you need to process the images later.
Craig Versek of PVOS had the idea to use a Raspberry Pi and a webcam to wirelessly stream images back to earth. The Pi is ideal because it’s lightweight and takes relatively little power.Here is a system description and a writeup (with video) of their first launch.