David Williamson's amazing videos are so short that you can download them even if you have a slow dialup connection. Just right-click and "save as" --remember where you save them. I keep telling David that the copanies that make straws should be paying him for all the new uses of straws he finds.
This one is a tiny kite that flies around indoors on a table top, pulled around by a robot going around in circles.tinykite
This one is a steam engine. The boiler really is made from a light bulb (thanks to our mutual friend Jeff Bindon for that idea), the piston is made from a balloon, flywheel from a cereal box, cranks from paper clips, etc balloonSteamEngine
Here is the steam engine on the move. steambug
David's latest interests revolve around clocks: both escapement and water clocks. Link to David's clock page
Here is a propeller car made from straws
Here is a robot that David made which flaps, creating suction, sort of a reverse hovercraft which hovers on ceilings instead of floors. Here is an electric version of it.
Here is finger, a variation of my robot hand project, made just from a straw and slit so many times that it's more like a tentacle than a finger--almost creapy! teenygrip
Here are some vids of balloon locomotives newloco and newloco2
Here he has made a track out of straws
These are still pictures of a mobile made from straws--so humble, yet so gracefull picture1 picture2
David's web site is here http://www.geocities.com/davidvwilliamson/