I met Sir Stirling Moss briefly. I was at the Mille Miglia in 1990, and hanging around Breschia for the "tech". Which mostly consists of revving the engine and tooting the horn, very Italian. This was back when Mercedes still let 300 SLR #722 out to play (it's a replica now) and Sir Stirling was driving it.
On the way back to the hotel, we were passing the big Mercedes dealership on the edge of town. On a whim, I wheeled into the lot and around back. In the garage was #722 and a Gullwing, getting fettled for the upcoming rally. I stuck my head into the showroom and Moss was sitting in a corner at a quiet table, away from the chaos that had reigned all day in the town square. I said a quick hello and walked away with a signed poster from the event.
Can't remember who else I've met. Well, I went to high school with Alanis Morisette, but she was just Alanis the teenybopper pop queen at the time and wasn't exactly an idol.