Check out Umphrey's McGee with guests Mad Dog's Filthy Little Secret Horns take on the Chicago classic "25 or 6 to 4" during their NYE show at the Pagaent in St. Louis, MO. And Jeff Waful's lights? Ridiculous.
Here's another ambitious and impressive cover from a month earlier -- the Rolling Stone's "You Can't Always Get What You Want" with the Chicago Mass Choir.