VIRAL VIDEO OF THE DAY: Got 12 minutes to kill? Check out Alex Chadwick of the Chicago Music Exchange as he straps on a 1958 Fender Strat and fast-forwards his way through 60 years of mostly iconic rock & roll riffs, starting with the 1954 pop standard "Mr. Sandman," and concluding 99 riffs later with St. Vincent's 2011 single "Cruel." Credit to Gawker, which posted the clip, and to Rock Rap Confidential, which spread it around. (7/5a)