Poking around the internet I found this, the lead track from a tribute to Joe Strummer album called Shatter The Hotel, all the tracks being reggae and dub versions of Clash songs. It's actually pretty good with several standout versions and worth tracking down if Clash covers are your thing. You can get it at emusic and on Amazon. The album's proceeds go to Strummerville which supprts several worthwhile Strummeresque causes. If you like the Easy Allstars cover albums of Pink Floyd and Radiohead chances are you'll like this too and many of The Clash's songs take easily to dub and reggae-isation. This one is London Calling, covered by Dubtronix ('Dubstep, future garage and beyond' his website says, and hopefully 'weddings, parties, anything, and bongo jazz a speciality' as well), with the great Don Letts and Dan Donovan (currently playing keyboards in reformed Big Audio Dynamite) guesting. Skanking.