Hmmmn... I auditioned for a part in The Lord of the Rings, and my Girlfriend's cousin was an Orc (not sure which one tho'!). And she used to walk the dog of the guy who played Deagol.
But then, we're Kiwis, and I think most of New Zealand knows someone who was part of LOTR!! Don't think they're cachers tho, so no, I don't know any famous cachers!