Here is a pretty cool program for you Mac users with a PSP. Ry sets up a server on your Mac that will let you control iTunes and DVD, as well as read your email and look at your clock. It is still in early development but I have a feeling this will go far.
I remember a while back I made something similar for my Xbox. I used XBMC's webserver and my PSP with a custom webpage to control everything in XBMC. It was pretty nice to use my PSP to watch videos and listen to music on my Xbox.
But If you have a Mac and own a PSP, check it out.
Ry