Sent to you by mike via Google Reader:
baronvoncarson tips news that today Valve released an updated version of Alien Swarm, a popular Unreal Tournament 2004 total conversion mod. The creators of the mod were hired by Valve, and they've helped turn it into a stand-alone game running on the Source engine. Valve is also releasing the code base for Alien Swarm and an SDK. The game is available for free on Steam.
Read more of this story at Slashdot.
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