Stumbled across Charlie Kelly's website, and these pages are too good not to share.
http://sonic.net/~ckelly/Seekay/weird_bike_stuff.htm
http://sonic.net/~ckelly/Seekay/weird_bike_stuff2.htm
I've been riding since about 1990, and other than the 2WD bike, I hadn't seen any of these bizarre contraptions before.