I ran into Val Kilmer once. He was as scuzzy and abusive as you’d think he’d be. (Not to me…he was yelling at a production assistant.) Later I figured out that he was filming “Wonderland” (playing John Holmes in the movie about the Wonderland murders), so maybe it was just some of that Method Actor stuff, but…
And Drew Barrymore? Loud, crude, and obnoxious as hell. I saw her at a showing of “Donnie Darko” at the Arclight. I’m told she doesn’t drink and drug anymore, but she sure acted pretty wacked out.
Charlie Kaufman (the screenwriter who just won a AA) is a quietly self-depricating guy. I’ve seen him at a couple of Q&As at the afformentioned Arclight Cinema, and I see him occasionally at the grocery store. He doesn’t look much like his character in “Adaptation” (he’s short, slight, and has a full head of hair) but I can imagine him thinking those monologues.
I don’t know about famous, but there are several has-beens I’ve run into in Pasadena, including Wil Wheaton (the kid who played Wesley Crusher) who has a smashing girlfriend/wife, and that dude from “The Pretender”, who hasn’t worked on anything since. Actually I keep seeing him (4-5 times) at a gas station near my house, so I think he might be stalking me. 
And then there was the night when I was running through one of the ritzier parts of Pasadena; I ran past a walled mansion when the driveway gate opened and this guy wheeled out his trashcan. I thought to myself, “He, that guy looks like David Lee Roth, only his hair is shorte…”
Yep. I saw Dave, taking out his garbage. I’m not a Van Halel or Roth fan, but it’s nice to know that the rock stars are mere mortals just like the rest of us.
My Hollywood experience just won’t be complete, though, until I see Jack Nickelson beating the crap out of someone with a golf club on the side of the road.
Stranger