bizarre pedal powered things

Bicycles are very efficient machines, more efficient than legs! Here are some of the more bizarre bicycle powered objects from a washing machine, to a bulldozer, a centrifuge at NASA and even a rollercoaster.

 
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This is one of the most wonderfully quixotic things we have ever seen, the combination of the gentle art of recreational cycling with the thrills and spills of a roller coaster.
Treehugger has a great list of whimsical bicycle lawnmowers, which are just about practical looking.
A wheelchair is not an item you would expect to be pedal powered, but there you go. Such an item does in fact exist and has proven useful in rehabilitation.
The Center for Biological Research have developed a human powered centrifuge which allows a subject to pedal the mechanism around at 50 rpm, creating a force of up to 5G.
Not only is this Lamborghini slow and efficient but it is entirely transparent, being made of a wireframe enclosure, like an unrendered 3d model.
If you look around the web there are in fact a surprising number of pedal powered washing machines, presumably since the spin mechanism is easy to create and doesn't need a critical power threshold to work.
To demonstrate the idea that LED lights are more energy efficient, this billboard had a giant illuminated Christmas deer decoration which was powered by a real person cycling alongside.
To go along with our list of exoskeletons, here is one that is actually pedal powered.
The site linked to here has some very nice pedal powered tools for sale, such as this wonderful jigsaw.