At the Grammy awards last month,  performed their song 'One' with classical pianist Lang Lang, and now a recording of the rehearsal performance is available as a digital download.

The rehearsal version of 'One' is now available for purchase at iTunes for $1.29. A portion of the proceeds will benefit the charity MusiCares.

And while fans are happy to have that version of 'One' and the live songs from the 'Through the Never' soundtrack, the big question is when Metallica will release new material. In a recent interview, Lars Ulrich didn't shed much light on the matter.

“What I can say is, we’re one day closer to the next record being released than we were yesterday," Ulrich says. "Unless there’s what’s called an ‘Act of God,’ I would hedge my bets that ’201′ would be the first three digits in the release year. And I don’t know much beyond that. We’ve been jamming along. We’ve been putting in some time.”

Guitarist Kirk Hammett has been busy with his inaugural Fear FestEvil horror and music festival, which took place over the weekend. During the event he jammed with his former group Exodus and Death Angel. With Exodus, he played ‘Piranha’ and a cover of Blue Oyster Cult‘s ‘Godzilla.’ With Death Angel, he sat in on covers of Black Sabbath‘s ‘Heaven and Hell’ and Metallica’s ‘Trapped Under Ice.’

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