Yep, Dwight Clark probably has the best autograph in the NFL, and quite possibly in the entire world. I recently caught wind of a post on the NFL sub-reddit. User JoeB_302 had a chance to meet Dwight Clark, at an event at a car dealership.He got Clark's autograph and it featured a diagram of Sprint Right Option.
Even though this was part of a sponsored event, it is still a fantastic autograph. If I get a chance to meet him again (I met him at CSN Bay Area for the 49ers-Lions game back in 2011, but did not ask for an autograph), I might be inclined to get this autograph. I would generally prefer the picture with the player, but that's one very unique autograph!
I don't have many autographs. My favorite is probably that of Hulk Hogan. I met him in an airport when he was waiting to get on the same flight I was on. He ended up signing autographs and taking pictures with people for a solid 30 minutes. He was very generous with his time.
Anybody have any fun autograph stories, or general celebrity encounters?