Robert Downey, Jr plays billionaire Tony Stark in the Iron Man and Avengers movies. This might be the best casting for anything every. Robert Downey, Jr (or RDJ for the rest of this post) is actually cooler than Tony Stark. Because RJD is real. He's everything that a fictional charecter would want to be...except the whole super-hero-metal-suit thing.
Here's more evidence:
RDJ joined Sting on stage, and KILLED IT: