PlayStation Portable/Homebrew

I want to get a PSP, which one do I get?

A year ago, the answer to that would've been "A big old PSP-1000 (Fat) and a huge-ass memory stick". However, with the cracking of the PS3's Master Key (and thus the ability to sign things so that the PSP's stock firmware (AKA official firmware or OFW) can run it), things have changed. While technically only the PSP-1000 and certain 2000 (slim) models are fully hackable (able to flash a custom firmware (cfw) to the device proper), any PSP can run a "light" custom firmware like LME, and the only difference is you have to run it after booting up, instead of having it boot in to the firmware. As such, if you have no PSP right now, your best bets are the PSP-3000 (if you need to play UMD games) or the Go (if you don't).