To help me mock up user interfaces on the Balloon, I've written a little 
program called fbconvert which knows how to convert raw images into a 
format suitable to copy into the Balloon's framebuffer. It should work 
for mono and colour LCDs, and is described at:
http://www.balloonboard.org/wiki/index.php/LCDTesting

I hope this is useful to someone,
Chris