oh my, tanya, i just figured out what you meant by hte thing sticking off the back of the bike....all my entries up to this point were of an actual bicycle, not a stationary bike, so the 'tag' was the back axle point of the back tire ( the tires were the C and the O) :)
anyway, here is one that incorporates a stationary bike instead of an actual bike.
(This comment references Entry #101)