Wolfenstein 3D is now playable as a free-to-play browser game.
From Bethesda Softworks
We're marking the 20th Anniversary of Wolfenstein 3D, the original, and now legendary, game that launched the first person shooter genre by releasing a free-to-play browser version of the game. You can now play the classic PC game directly in browser at: wolfenstein.bethsoft.com or on the Wolfenstein Facebook page at www.facebook.com/wolfenstein
Later today we will also be offering Wolfenstein 3D Classic Platinum, available on the iPhone, iPad, and iPod Touch, free for a limited time.