I'll throw in a weird one just for grins and the French fans: Simplex all-metal stuff from early '80s such as the SX660 RD and matching FD with friction levers. It's remarkably similar to early SunTour slant-parallelogram and Shimano in both appearance and function...durable little buggers, too. Only (very minor) downside is the RD uses the Simplex bolt/nut to mount it to their unthreaded DO, but this is an UPside if you have a French (Swiss or Austrian bike) with a Simplex dropout, and the RD can also mount in any conventional threaded DO hanger, too. Much cheaper than the ultra-desirable Super LJ, and with only a little weight penalty.