You can play PSP isos on a Vita if you have either ECFW or VHBL on it. Basically, if you were to get one of the two, it would be as if you had a modded PSP, so you could play PSP isos, PSP homebrew, etc. The only problem is that they have to exploit certain games for it to work, and right now, the most recent game this is possible on is UNO, which got taken off of the Playstation Store 2 days after the exploit was released since there's tattle tale bishes on the Playstation forums. Wololo.net will keep you updated. Best thing to do if you're serious about this is put at least $10, or maybe $15 (just to be safe) on your Playstation account, so when they announce the game they made the exploit for, you can download it before they take it off. And there is some info on that website about a possible hack of the actual Vita on there.