But anyways, this is a project I liked the most:
Department where I was majoring had this old and crappy MRI scanner. It was pretty much useless since the console and all the signal processing hardware were non functional. The only things that were working were the electromagnet, gradient coils and RF coil. To revive the machine a friend of mine set up an oscilloscope and arbitrary waveform generator to do the work for the missing hardware. I had an opportunity to play with it and wrote a software in C++ that controlled the hardware to produce usable signal which was then processed further to produce scans.