Mine would have to be SMG (Jean Frelat) from the late 70's to late 80's. He built frames mostly using the bronze fillet-brazing technique. They were organic in my opinion, like avant-garde sculptures. Frelat - always a patriotic man who snubbed Reynolds and Columbus tubing (though he did build a few frames from the latter) - put his trust in French tube makers such as Vitus and the lesser known Excell and Cadus. He was particularly fond of aero shaped tubing with internal cable routing and socket style internal seatbolt clamps with 'fastback' stays, putting him ahead of his time. He passed away in 2009 aged 80.
So, what about you?
So, what about you?