I guess my derailleur "eye candy" pic would be very predictable to many here:

Mavic's 80's SSC 851/860 derailleur set. Commonly known as the "Erector" style derailleurs from Mavic. fully servicable, but I seriously doubt if anyone who did not race professionally on these had really broken down theirs to replace worn parts, but it's nice to know you could, if it ever does wear out or gets damaged.

Kinda falls in the middle of the 80's derailleur shifting performance spectrum, but it sure stands out when it comes to looks different from all the others!

Would the sharp, angular shapes on this derailleur earn it "hard eye candy" status??

Chombi