In 2002, the first cheap digital cameras had already appeared. My brother was not content with the Windows-only driver situation of an Agfa CL20 and reverse-engineered a Linux driver for it, together with a Finnish guy whose name I can't remember... The driver was later incorporated into the popular gphoto framework, so it's now used on all Linux boxes.
Reverse-engineering serial communication over USB (using hex dumps) is quite interesting and teaches one things about image file formats. I helped a little bit and made a website, which is rather historic by now.
My most significant contribution to the project was the creation of an animated GIF image, merely 18kb in size.
The driver even got a webcam mode. A few years later, I had the camera on the balcony for a few months, observing breeding blackbirds. A great experience that I can recommend! [hilarious video snapshots to be inserted here]
