Devil Summoner: Soul Hackers is a game originally released back in 1997 for the Sega Saturn in Japan. It was a sequel to Shin Megami Tensei: Devil Summoner, itself a game within the same Megami Tensei universe inhabited by the Persona series. Publisher Atlus has tried a few times to bring the title to the states, but Sony hasn't yet allowed it, so a group of fans calling itself "Devil Hackers" is working on a fan-made translation of the title, playable on the PSP.
You can watch a "teaser trailer" of the translation after the break -- but someone needs to translate the word "teaser" for the Devil Hackers, because it's thirteen minutes long. Assuming things work themselves out, fans interested in playing the game in English should get their chance soon.