Have you met a celebrity? who and how did they act?

I work at a large airport for an airline and see celebrities fairly often, the worst was Nicole Richie, she insisted on sitting in our supervisors office so she wouldn't be "hared" and just texted the whole time, the nicest is Vanilla Ice, he will always stop what he's doing to be nice to fans and gave his seat up for an oversold penger.... do you have any experiences?