Not really a dumpster find, but my No1.:
The owner of a local bike shop started a few years ago to put old parts
he thought are still saleable in a large old wooden apothecary cabinet
behind the counter. To find parts he has nailed a part onto the outside
of each drawer: A Mafac brake on the drawer containing brakes, A BB axle
at the BB drawer and so on.
After several weeks rummaging through the cabinet I took a closer look
at the Nouvo Record derailleur which was nailed to the drawer containg
derailleurs:
http://bulgier.net/
No.2 is a 1962 Cinelli Mod.B I found at the bicycle stand of the local baths I already told here on the list.