The PSP Go (PSP-N1000, 2009–2011) was a digital-only, sliding-screen redesign. Features & limits today:
Only buy if: You want the form factor, have CFW knowledge, and own a PS3/PSP to transfer purchased licenses. Otherwise: PSP-2000/3000 + large Memory Stick + CFW is superior (UMD, replaceable battery, video out, cheaper).