Metal giants Metallica have recently shared a web URL with a mysterious countdown clock that ends this Thursday, October 10th at Noon ET. With the 20th Anniversary shows of S&M, their full symphony orchestra live album, we are only left to wonder what the clock is related to. On October 9th, the band is having a one night only screening of their recent S&M2 shows in San Francisco in 3,000 theaters across the United States. Click here to check out the mysterious clock.