U2 have debuted a brand new song online. The song - 'Invisible' - got its premiere last night during the Superbowl and, as part of a new partnership between Bono's charity (RED) and Bank of America, the song is available for free download from iTunes for 24 hours. Not only that, Bank of America will donate $1 to charity for each free download of the tune. Check out a preview of 'Invisble' above.

'Invisible' is produced by the excellent Danger Mouse and mixed by Tom Elmhirst. The video for the track is directed by Mark Romanek (Jay Z – 99 Problems; Johnny Cash - Hurt; Nine Inch Nails - Closer), 60 seconds of which will be shown during a Super Bowl ad break on 2nd February and on YouTube from 8:00pm GMT the same day.

New U2 music continues to trickle out ahead of the release of the band's 13th album sometime this year. Speculation as to when the album might be released is still rampant and, from what we can tell, the smart money is on somewhere in the region of April.