Progressive jam band Umphrey's McGee celebrated their 25th anniversary by playing a three-date residency at the Riviera Theatre in Chicago on the last three nights of December. The band's regular drummer Kris Myers is recuperating from a shoulder injury and was unable to perform at all three shows, so the band recruited several guest drummers to sit in, including Dream Theater's Mike Portnoy. Portnoy sat in for the December 29th show on covers of Pink Floyd's In The Flesh and Another Brick In The Wall, The Beatles' You Never Give Me Your Money, and Abacab by Genesis. He also sat in for the encore, which included a cover of Spinal Tap's Big Bottom (!!) and Rush's YYZ as seen in this video (YYZ begins around the 7-minute mark).