Character actors blend into the background for our sins

I saw Juno last night, and it was pretty darn fine. Considering how boneheaded most of America is these days in regard to touchy subjects like abortion and teen pregnancy, it's a wonder any sober discussion of the subject can rise to the surface, let alone something as funny and cutting as this film. This is the second movie by director Jason Reitman that I really enjoyed (he did Thank You for Smoking), and it depresses the crap out of me that he's two years younger than I am. Not that I want to be a film director, but you know how it is.

But one of the best things about it is J.K. Simmons. He plays the title character's father, and he is awesome. I've always had a fondness for character actors, those people who appear in 8,000 films yet somehow get to stay fat and ugly (or at least normal looking). They're usually better than nine tenths of the actors they're working with; since the tabloids don't give a shit about whteher they're gay or have a fat ass, they get to focus on, you know, actually acting. Some of my favorites:

J.K. Simmons (J. Jonah Jameson in Spider-Man, the psychologist on Law & Order, the Shaggy Man on Justice League)
John Amos (the dad on Good Times and in Coming to America, Adm. Fitzwallace on The West Wing)
Peter Scolari (the guy on Bosom Buddies who wasn't Tom Hanks)
Wallace Shawn (My Dinner with Andre, the "Inconceivable!" guy in The Princess Bride)

See, this is my problem—now I can't think of any others. Suggestions?