The Tonight Show's Jimmy Fallon and house band the Roots have been having a pretty great week. Earlier this week, the show hosted disco savant Giorgio Moroder behind the keys in a special cameo performance. Last night, both Jimmy and the Roots made their own cameo appearance at U2's Madison Square Garden show. While Jimmy joined Bono for renditions of "Mysterious Ways" and "Desire," the Roots hopped on for "Angel of Harlem." As if that's not enough, Billboard reported Sir Paul McCartney, Alicia Keys and Nile Rodgers were also there. Watch the whole thing go down below.