After successfully porting the Naughty Dog PS2 classic, Jak and Daxter: The Precursor Legacy to PC last June, the OpenGOAL team has now done the same for its edgy, GTA-influenced sequel, Jak 2 (Jak 2: Renegade for you PAL region kiddies). Though still in beta, Jak 2 is playable from start to finish through OpenGOAL.
This is distinct from just running the game on an emulator: the OpenGOAL team reverse-engineered the games to run natively on PC, avoiding the need to emulate a PlayStation 2 at all. The OpenGOAL project is completely legal on a similar basis to emulators, however, as it was built from the bottom up without incorporating any proprietary Sony or Naughty Dog tech—you need an ISO image from your own copy of Jak 2 to use with OpenGOAL's launcher.
The Jak and Daxter games were made in a unique programming language, GOAL, that doesn't seem to have been used anywhere else. The OpenGOAL team seems to relish the hurdles inherent to mastering such an obscure cul-de-sac of tech history. In addition to aiding in the preservation and understanding of these games, OpenGOAL's FAQ describes the project as being primarily motivated "for fun and challenge."
While Jak 2 is "100% completable" through its OpenGOAL port, there remain some bugs for the team to work on. After that, they seem dead set on completing the PS2 trilogy with a Jak 3 port, though they don't seem totally sold on one for Jak X: Combat Racing just yet.