Hack it, you'll get more money if u turn it into a snes, megadrive, etc emulator and fill it with games
depends on which model it is due to sony changing the motherboard over time making some models very difficult if not impossible at the moment since the only two ways to hack it are a Pandora Battery coupled with a Magic Memory Stick or to use software exploits in either the firmware itself or through the use of demo's and games.
PSP 1000 (Launch Units): Fully Hackable via use of both hardware and or Software
PSP 2000: Early Models with Hardware, Other models require software exploit
PSP 3000: Software Only. Newest Retail Units Are Pandora Proof
PSP GO (4000): Software only via half byte loader due to lack of UMD Drive, Non Removable Internal Battery. and only M2 Memory Sticks are supported.