Datel announced a new 4GB PSP Hard Drive for PSP, which has four times the capacity of the 1GB Memory Stick Pro Duo, and it has a built-in 3600mh X2 Batter Pack, which provides twice the battery life to the PSP, at a cost less than a 2GB Pro Duo Memory Stick. The unit also comes with a Get Connected Media Cable and media software. The PSP 4GB Hard Drive will be released in Europe on October 20, for £149.99
So hell with 2gb pro duo shit, 4 times 1gb + double time normal batterie.
Yes, it will stick out of the psp from both the left and the right side (What i call a fat ass, lol). So you wont be able to put it in any of the normal cases