http://technabob.com/blog/2009/11/09/catena-bike-chain-clock/
Here’s an unusual concept for a wall clock. Instead of telling the time with hands or a digital display, the Catena clock tells time along the perimeter of a bicycle chain.
Designed by Andreas Dober for Germany’s Anthologie Quartett, the Catena (Latin for “chain”) has a certain retro-steampunk look about it. Time is told using copper digits mounted on the outside of a bike chain that rotates around a single motorized gear. Now don’t bother trying to tell the exact time with this. The only numbers on the chain are the hours, so any attempt to figure out minutes is a crap-shoot.
While I dig the grungy minimalism of the clock, I don’t dig the $2300+ (USD) price tag. But I suppose if you’ve got really deep pockets, you can order one over at Unica Home.
On the other hand, I won’t tell anyone if you decide to make your own out of $20 worth of junk you find at a flea market.