lol

ive found this... and am goin to purchase one in the future...

http://www.estormuk.com/html/memory___storage.html

scroll down a bit once loaded....

and u'll find the 4Gb Sony PSP Memory & Battery Solution

which apparently is

NEW Clip On PSP 4 GIG HARD DRIVE & HI CAPACITY BATTERY WITH USB TRANSFER KIT

anyone got one, heard about it or used one???