I've no idea, but I suspect the ones that will be considered classics are the ones the younger sorts are riding now. For example, I expect a billion Bianchi Pistas to show up in thrift stores in about five years, and then they become collectible in twenty because most of them are sent to the scrapyard because all the hip sorts five years from now will be riding recumbents or tricylces or whatever is hip in the near future (it won't be fixies).
The obvious ones are things like the Rivendells and the smaller makers (Alex Singer types). But they may be recalled more as niche bikes than anything else, due to their smaller runs.
It is my personal hope that old French bikes become very hip, so I can sell my collection for several million dollars and then buy them back for a fiver when the market bottoms out. However, I am not counting on it.
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