Tripwire Interactive, the studio formed by members of the team responsible for the award-winning Unreal Tournament 2004 mod Red Orchestra, has picked up Teotl Studios' award-winning Unreal Tournament 3 mod The Ball and is running with it.
What can a bunch of amateurs turn Unreal Tournament 3 into? The just-completed Make Something Unreal contest offered money in order to find some answers. One is the shot top this post, but that wasn't the winner.
Everyone else is using the Unreal Engine 3 for game development, so why shouldn't you? Epic Games has just released the Unreal Development Kit, a free edition of the Unreal Engine 3 for everybody.