At Christmas I bought a [PSP] and since then I've only really used it to play games - I guess that was the primary reason to get it... but I'm about to go on a long flight and not trusting the entertainment systems / waiting around at [George Bush International] I thought it was about time I put a few movies on there. I'm a bit of a linux head (I'm primarily a [Ubuntu] user), if you hadn't already guess and I wanted to do it on here. In fact assuming you have [ffmpeg] installed (its in the Ubuntu repo) its fairly simple:
ffmpeg -i "InputFile.avi" -f psp -r 29.97 -b 768k -ar 24000 -ab 64k -s 320x240 "OutputFile.mp4"
then just copy that over to your psp memory stick (assuming it is mounted as disk):
cp -r OutputFile.mp4 /media/disk/VIDEO
Job done. 
