Campagnolo C-Record in general. I still love it, though I'm not ignorant to its shortcomings. The Delta brakes were heavy, went through several iterations, and were finicky to set up. The smooth slope of the spider on the crankset can get marred by an over-shift. The clipless pedals from this period were never on par with competitors pedal options. Beautiful finish, excellent quality bearings/races, but over-priced then and now.

Edit: Oh, and I forgot to mention the Synchros shifters. I don't have any experience with them, but Sheldon had the following to say: "Synchro derailers and shift levers are incompatible with anything else, and the Synchro system worked so poorly that it is not a good idea to try to set the system up on a bike you intend to actually ride."