I know that by definition the GSX-R isn't rare considering how many were produced, but I would say they are close knowing how hard it would be to find a survivor like this one. Take a look at this 1988 GSX-R 1100 for sale in Chicago on Craigslist:
quote from seller's Craigslist ad:
THIS IS A 1988 GSXR 1100 IN EXCELLENT CONDITION. IT HAS AN PROFESSIONALLY 1109 BIG BORE KIT INSTALLED IT HAS 2200 MILES ON IT.THIS IS AN EXTREMELY FAST BIKE. THERE IS 38mm FLAT SLIDES ,BIG BORE KIT, FALICON RODS AND HEAD WORK IN THE MOTOR. AND THERE ARE ALOT OF GREAT FEATURES SUCH AS IT HAS 8900 MILES ON THE BODY AND THIS IS A REALLY CLEAN BIKE.
Love the colors, original plastics, dual lamps and recently built motor. But that $3500 asking absolutely rocks!
Update: This post is pretty outdated. Check out these GSX-R 1100's on eBay right now: