Chris Barrie (Red Dwarf), Kenny Baker, Jools Holland. I was working at the time and couldn't really speak to any of them, not that I especially wanted to.
At sci fi conventions/events: Robert Picardo, Bruce Boxleitner, Andreas Katsulas (he hugged my Mum, I was so proud) and the whole cast of B5 except the blonde woman whose name currently escapes me. And whoever it was in the lift at the event hotel, who gave me nods and encouraging smiles but who I didn't dare speak to because I wasn't sure who she was (one day I will figure it out and kick myself). I won dinner with Nana "Kira" Visitor, but was stood up (dammit).
I stood at the stage door once to meet the Indigo Girls, they were lovely but to date I could never explain why they signed each other's names on my flyer. Go figure.
Queen Noor from Jordan, who I didn't recognise and wouldn't recognise again. She was just a blonde lady who was very nice.
Edwina Currie - a British politician. She was a ***** and she uses a fuckton of hairspray (one of those awkward moments where you meet someone in the ladies room).
My favourite will always be Claudia "Ivanova" Christian, so sweet and funny and charming.
Oh, and Jeri Ryan answered one of my tweets which made me giddy.