Right now I'm facing what I'd consider the most outrageous case that I've been involved so far: A manufacturer of Linux-based embedded devices (no, I will not name the company) really has the guts to go in front of court and sue another company for modifying the firmware on those devices. More specifically, the only modifications to program code are on the GPL licensed parts of the software. None of the proprietary userspace programs are touched! None of the proprietary programs are ever distributed either.