I have been blessed and have met a lot of different types of "celebrities".
Sports: we live in sports town and many of my friends parents worked for the organizations and one of my jobs also brought me in close contact with many of the players: Most memorable would be; O.J. Simpson, Jim Kelley, Marv Levy, Dan Marino, Dave Andrechuck, and Danny Briere. My father was very close friends with Tom Sestack and Paul McGuire.
Movies, TV, etc: Paul Newman, Jim Carey, Drew Carey, Ryan Stiles, Wayne Brady, Sinbad, and Steve Colbert.
Political: President Obama, Michelle Obama, and Jack Kemp.
Musical: Quite a few through my daughter but most memorable: Goo Goo Dolls, Prince, Beach Boys, (John Stamos but very briefly), All Time Low, Cute is What we Aim for, Maroon 5, etc.
Many were quick meeting while some were longer. With work contacts I had face to face meetings and then numerous phone calls.