I've met Peter Mayhew on at least two different occassions. The first time was around 1996 or '97; both times were in Plano, TX at a sci-fi convention. I remember the first time I saw him. I was standing in line outside in the parking lot, waiting for the building to open, and this tall, skinny guy walked past me. I had no idea who he was, since I had never seen him without a costume on.
That was my first sci-fi convention experience. I'll be posting more pics from all those that I attended in Plano in future posts.
I had someone in line behind me take this picture:
Here's one I took of Mayhew and my wife, probably in 1999: