He's been in so many movies that I'm sure you recognize his face, if not some of his more notable characters - like Dr. Connors (a.k.a. the Lizard) in the Spider-Man films or Owen, the redneck, in Planes, Trains & Automobiles. Of course, many people rightly associate him with his brilliant, career-making turn as Dr. Bill Maplewood in Happiness. It was a phenomenal, as well as incredibly brave, performance.
I think he's great!