Well isn't this a treat. Earlier in the year for Record Store Day Feist and Mastodon released a version of one anothers' tracks after a chance meeting on the BBC's Later... with Jools Holland. Mastodon tackled the Metals featuring track "A Commotion" whilst Feist took on Mastodon's "Black Tongue" from The Hunter. Today a video for "A Commotion" has hit the net and it's an interactive video that features a crossfade letting you manually flick between either version of the song. It's pretty darn cool and you can play with it over here.