John Anealio has some free remixes of his "Angry Robot" song on his blog, Sci-Fi Songs. The remixes were created by others as part of a competition. The songs below were remixed by Dale Chase, Denis Cherryman, David Ritter, Mike Crooker, and Chooch Schubert, respectively.
Check out the songs below or click here for the posting on his website and for more information.
Here's Anealio's original song: