Knife bikes
Back in August we had the Maniago knife festival. The coolest things I saw were the old knife sharpening bikes the tradesmen would ride to different town markets. Imagine hauling that whetstone around!
Check out the drive for the stone. Just pop the chain off the crank and hook up the second chain between the drive and the crank. The second chain isn't there, but your other chain would be around the chainstay, and I don't think they had removable links!
The bike in action.
Here's another knife sharpening bike. The sign said it's from the 1940s - 1950s, but...
Check out the carbide headlight and taillight. More like the 1920s - 1930s.