User-made content (a.k.a. Mods) for games has always been an area where PC gamers have had an upper hand over console gamers. These ‘mods’ allow access to additional content made by freelance or amateur developers for the gaming community; so, if you own a PC game with a free SDK (software development kit), chances are you will be able to boost your game time and gain full value for your money. According to what Epic games has speculated that PC Mods could be accessible on the PS3 version of the Unreal Tournament 2007 . If they do manage to implement this it would be a big step for console gaming.
As of now, mods are still limited to PC games. With that being said, 3D Realms and Human Head have released an official SDK for Prey which will include “all of the game code (for building your own Game DLL), as well as some code examples/tutorials which will explain a few of the basic things you should know before diving into the code-base_._” Here is a link to the SDK download.