Hi, let me give you an American spin, in no particular order. (though I did pass Fergie in the toy section of Harrods about 5 years ago)
Met and or/knew a lot of people since I worked the shows and movies for a long time. Worked with Dustin Hoffman (I was prepared to not like him, but he was great) John Malkovich, Steve Lang, Nick Zorich, and Arthur Miller in Death of a Salesman for about five weeks about 22 years ago. Also, hung out with in high school, (and asked out but she turned me down) Amy Maddigan. Met Gina Davis, Meg Ryan, David Hasselhoff, Matt Brodrick, Gene Hackman, Rick Moranis, Bill Murray, The Association, Chad and Jeremy, and lots of others I can't remember. Martin Short asked me for dirrections downtown one day, and I knew who he was and couldn't think of his name(!) Also dated a girl who was best friends (at the time) with Jim Morrison's (of the Doors) sister. Funny thing was that I went to high school with the first cousin of Ray Manzarek of the Doors. Still now very good friends with one of the Chieftains. (actually, supposed to go out with him tonight for a drink)
Oh, also recently met Jimmy Carter, though I've seen all the presidents now living, not counting this present thing we have. Also, worked a detail for Prince Charles when he was in Chicago. Shook hands with Mulrooney from Canada at one time, and a few presidential candidates as well. Oh, and Joan Baez. Actually knew her husband for a bit in California. Long story.
Other than that, not many.