This is the palmpsone, it is a modified version of the original Ps One [mods it's legal, it's not for sale], that looks just like the psp but a little bigger, you can check the webpage here http://www.palmpsone.com/and here are some pics:
I would kill to have one, it is really awesome; it also gives a little tutorial if u want to do it yourself ;).
And this guy as well made a portable SNES system! Imagine playing Super Mario Classic on the Go! This is the webpage http://supernes2go.com/