Movies on your sony PSP !
It seems that according to this great how-to from engadget:
http://portableaudio.engadget.com/entry/1234000980024404/
That Sony don’t want us to be able to “properly” watch videos on our Sony PSP from the memory card. It can be done however the PSP doesn’t allow you to encode video to fill the entire resolution. With UMD’s at the silly price of $20 - $30 this is a shame as i quite like the idea of the PSP as a PVP aswell. I guess we will just have to make do with a smaller screen 
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