While the Republican party's candidates for this year's US presidential election sink into an increasingly bitter campaign and insist on saying mad stuff about abortion and being exposed as paying naff all tax, President Obama has been having a nice time doing impromptu Al Green covers during speeches. What's more, Rolling Stone has spotted that the canny PR operative has now made the cover available as a ringtone over at his official website. Next to download! Blair does Bolt Thrower!