Slightly off topic, given that it’s not in MP3 format, but let’s go three for three and close the week with another open-source remix challenge (yesterday’s entry on Wired magazine’s contest here, and the day prior’s entry on Recon’s contest here). This one’s from the Chemical Brothers, whose “Galvanize” single is now available for cut’n’paste play as a promotion for their new album, Push the Button (have seven years passed since Money Mark’s album of that name?). Download the track’s vocal, by rapper Q-Tip of A Tribe Called Quest, and various preset Chemical Brothers loops. Fiddle about. Upload your finished version. Winner takes the latest edition of ACID Pro’s audio-production software and other treats. The files are in WAV format, which doesn’t require proprietary software to audition, and they range in length from one second to nearly 20, and in content from disco-ready beats, to humorously simple snare dashes, to tasty vinyl scratches, to extended (well, 18-second) snatches of atmosphere. It’s all at the acidplanet.com website, more specifically here. Contest ends February 21. In the meanwhile, log on and check out the entrants.