The Sorels -- four actor/dancers making like a New Wave version of The Temptations while lip-synching Dan Hartman's "I Can Dream About You" -- in Streets of Fire (1984).
First of all, those dance moves are just fucking great. And those guys are the snazziest dressers in rock-and-roll history; I'd wear one of those suits today in a heartbeat. Of course, it helps that the song itself is ragingly beautiful; it also helps that you don't see Hartman and his band doing it (you can find a clip of that elsewhere on YouTube, and you'll hate me if you do).
I should also add that until this morning I had no idea that one of The Sorels was the wonderful Mykelti Williamson, most recently of TV's Justified.
That's him, second from the right.