Few bands would turn down having Tony Iommi backing them up, and soon more bands will get the chance. The Black Sabbath guitarist has a treasure trove of riffs laying around, unused, in his studio. Queen's Brian May has inspired Iommi to put them to good use.

In a recent interview with Kerrang!, May talks about the riffs album the two were working on. "The idea was to put all these riffs out in some form so that people could build their own songs from them," he says (quote via NME.com). "You could make your own music with Tony Iommi on guitar!"

It's not clear how fans and musicians will be able to use these riffs and if Iommi is truly going to throw them into the public domain as it sounds like he might. There is no time frame for this unique project. Iommi has been busy with his Black Sabbath bandmates making '13,' their first album with Ozzy Osbourne in 35 years. Osbourne recently said that album could be the most important of his career.