Left 4 Dead 2 on PC is open to fan modification. Indeed, it's encouraged by Valve, who not only released the tools to enable gamers to do so, but even pledged to promote one user-created map each week for the foreseeable future. One such mod is 'Cold Stream' – a fan-made campaign set in a forest that's been picked up by Valve who have officially released it on PC after months in open Beta as a free download. As a first for Xbox 360, this very same fan-made content is coming to Xbox 360 on Friday.
For 560 MS Points.