I just found this on Slashdot, the pictures are excellent:
"With a budget of £500, Robert Harrison used [0]cheap parts,
a weather balloon, some duct tape, a digital camera, and a GPS device to
capture some great [1]photos of the earth from space that resulted in
NASA calling him to find out how he had done it. 'A guy phoned up who
worked for Nasa who was interested in how we took the pictures," said Mr
Harrison. 'He wanted to know how the hell we did it. He thought we used a
rocket. They said it would have cost them millions of dollars.' The
details of his balloon are as follows: he used 'an ordinary Canon camera
mounted on a weather balloon', 'free software' that 'reprogrammed the
camera to wake up every five minutes and take eight photographs and a
video before switching off for a rest.' He also ensured the camera was
'wrapped in loft insulation' to make sure it could operate at the cold
temperatures. The GPS device allowed him to pinpoint the balloon's
location, and retrieve the camera when it fell down to earth attached to
a small parachute."