One of the features not advertised by Sony, but widely advertised by PSP users/enthusiasts, is the ability to convert video files to a format which the PSP likes for watching on the go. I've scoured the Internet looking for "How would I convert videos for the PSP with one of my Linux machines?" - only to be skunked every time.
However, with all the tools for Mac OS X and Windows, I discovered a common theme. EVERY ONE was using FFmpeg. EVERY ONE. Well hey, FFmpeg was developed on Linux in the first place, right? How hard can this be?