My meets probably won't be as "cool" as some others may likely be, but:
First meet:
Smoked a blunt with the drummer of Australian punk band Phrenzal Rhomb, while playing a show in Houma, LA circa 96 or somewhere around there. Less Than Jake was the headliner, and afterwards we [the band I was in] ate at a hole-in-the-wall cajun restaurant with LTJ, although they thought they were too good to talk to us, even though (in my mind) we kicked their asses on stage because we had the local population on our side, and we were already known for riot-starting sorts of behaviors.
Second meet:
In Germany, some friends and I went to a He Is Legend show at a small venue and convinced Schuylar and Mitch (yea it was when Mitch was still strumming) to go drinking with us. Had an all-nighter. This was when they were touring with Norma Jean, and yes, Cory Putman showed up as well. I bought him a beer, can't remember what kind, I was drunk... Also saw him messing around with a girl in the guy's bathroom... as far as I knew at that time, he was both married, and a Christian....... dot dot.
Hrmm.. Haven't really met anyone else that anyone would know. Meaning, no one that really made it or anything. I think the best moment would have to be smoking a blunt with the drummer of Phrenzal Rhomb right before our show. Haven't kept up with them in ages, and I don't even know if they still have the same drummer... but guy, whatever your name is, if you're reading this, you rock.