Actors Jon Hamm, of Mad Men awesomeness, and Zach Galifianakis, whom you may remember from such films as The Hangover, have made a surprise cameo at Bonnaroo 2015 to enact a number of shenanigans on unsuspecting festivalgoers.
First off, the duo kicked off the annual Bonnaroo Superjam by performing a rousing duet of 1985 USA For Africa charity single We Are The World,…
