In 1990, at WDW, I saw Tammy Faye Baker in the stretching room of the HM. For a moment, I thought one of the ghosts had come back to life. She and her entourage had an escort and were being given a private tour. I saw Samantha Brown when she was filming the premiere lighting of the LED's on the castle at the MK. I've also seen Hulk Hogan, and the cast of Family Matters when they filmed one of their episodes on Disney property.
At Disneyland I've seen too many celebrities to mention, but my most memorable sighting was of Michael Jackson in March of 1993. I was riding the Peoplemover and it was coming out of Circlevision. I noticed a large crowd gathered in the Plaza and it was headed to Tomorrowland. I couldn't immediately figure out what was going on until I looked in the center of the crowd. There was a clearing in the center and it was Michael Jackson, wearing an outfit like you would see at an awards show. He was surrounded by three or four children, and there were several Disney "handlers" trying to keep space between Michael and the masses of people following him.
As I got off the Peoplemover I noticed this massive crowd of people headed towards me, and I tried to avoid it by standing right next to a support beam underneath the Peoplemover track. Apparently MJ thought it was also a good spot to try to avoid the crowds because he headed right towards me. For a brief moment he walked past me and it was just us. I waved and said hello, and he did the same. The crowds then gathered back around him as he walked by and they all headed towards Captain EO.
One of the kids that was with him had blonde curly hair and was wearing a brown flannel-ish top and pants. They almost looked like pajamas, and I thought that the kids must have been from Make-A-Wish or something. About a year later I saw a picture on the news of a kid with the same hair and clothes, but his face was blurred out. It turns out that the one of the kids he was with that day was the one who accused him of whatever it was he was accused of doing.
The thing I remember most is how small he seemed in real life. Yes, I know this happened at Disneyland, but I still can't resist telling the story. If you watched that whole saga on shows like "Inside Edition" and "A Current Affair", they would show video of MJ and the kid riding the Peoplemover. That video was taken later on the same day. I'm not the one who shot the video, but I was there and watched the craziness of the crowds.