Biggest thing for me was a swap of Cinellis. I had a 1972ish Speciale Corsa that was a bit small for me, I rode it in an Eroica CA or two, but It's smaller than optimum. By pure kismet, I ran into a guy who had a 1965ish SC in my size. It was too big for him, and mine was his size. One mutual inspection of frames later, and the swap was done. So he got the silver frame and I got the blue frame. We're both happy.
This one is now his.
This one is now mine, as built up by me.