BBG reader Guy Vardi passed along this wonderful video of the Waste of Time, a functioning grandfather clock made up entirely of old bicycles. It was built by Yedidya Vardi and Vladimir Zviagintsev, and it is on display at the Vardi Center for the Development of the Gifted in Israel. And here's the making-of video:
I love this quote from the YouTube description:
One of the design principles was to use only used elements. Edison once said that to invent you need good imagination and a pile of junk. The designers took his advice seriously.