Do cab fares count? I drove cab nights in Boston back in the late '70s-80's and a brief return in the early '90s. Some of my more memorable musician type elbow rubbing memories are:
Sitting on the Lennox Hotel cab stand reading my paper, the back door opens and a couple get's in. I put the paper down, turn around, open my mouth and blurt out "Oh my God...you're Elvin Jones!!". Turns out he actually already knew that, but got a kick out of my flipping out a little bit over it. It was him and his wife. They only went a short ride to Lulu White's in the South End but we had a great conversation on the way. I'll never forget that ride. For those of you who don't know him, Elvin was a legend of a jazz drummer.
Got a call one night to pick up at the Paradise Club and the entire New Riders of the Purple Sage piles into the cab for a ride back to the Sheraton Hotel. Right off they ask if it's OK to spark up. I gave the green light and out came a couple of enormous spliffs. Interesting ride. ;-)
Lessee...got a call at the Holiday Inn downtown and got the manager and two members of the Vapors who were a one hit wonder band ("Turning Japanese") back then. Took them out to WCBV TV station in Needham for a late night show, went in with them and hung out back stage while they did the show (with the meter running of course) and then brought them back to the hotel afterwards. Got pulled over by a Needham cop on the way back because something just "didn't look right" with the Boston Cab out in the 'burbs heading inbound with these three guys with the enormous '80's hairdoos on board. Good thing it wasn't the New Riders or there would have been big trouble. These guys were very straight despite the look.
Also used to pickup Mike Stern all the time whether he wanted a cab or not. I'd spot him walking down the street and pull over to give him a ride and pick his brain about his guitar technique. That ended when Miles Davis came into Michael's Jazz club one night to see Mike (Jacki Byard brought him in to see him) play and wound up hiring him for his band. That was the end of Mike being a Boston boy. Whoosh...off to New York.
Ok, that's it for the cab stories.