I've seen Mark around town a couple of times.

The first time I was shocked. I had just moved here and was looking for some curry paste, so I went to Ranch 99 in Mountain View. I turn around the corner, and bam, Mark Zuckerberg and his girl. We had this weird eye contact thing.

I walked around the store a couple of times, running into him again in a similar fashion (I didn't know where anything was at), and ended up being behind him in line.

Second time was in PA, I was just walking downtown to the Vans store, and same thing. Saw him on the street, made eye contact, etc...

Next time I see him I'll probably say hi, but nobody was bugging him. I guess I was surprised that somebody that high profile would be out and about, even in a place like SV.