The easiest one to hack would be the 1000, but the one that is still easy to hack and offers the most is the PSP-2000. You would need a pandora battery and a Magic Memory Stick. You could either buy them or watch a tutorial video on youtube explaining you how to make them. But, for the pandora battery, you might want to buy one(below 10$) or get a friend's hacked PSP to make a software modded one instead of doing the hardware mod. You should chek out www.psp-hacks.com and pspslimhacks.com for software and tutorials.