Sony's David Reeves said there was a trend among publishers to subcontract the development of PlayStation 2 versions of a next-generation game.
While producing a game for the PlayStation 3 or the Xbox 360 was initially difficult, there are already many experienced programmers for the PlayStation 2, Reeves said.
"You can set up your external company now, and in the next five years you can become a billionaire just developing for PS2."
