Pictured above: The natural result if you happen to not tighten the thumbscrew to hold the pen in place: HELLO WOR<ARRRRrrrrrrggggghhhhhhhhh>.
One of the interesting aircraft on display.
Some of the many electric cars.
Space-rated carpet treads on a mini-lunar rover to help it get traction in loose dust.
You can check out the full set of pictures on flickr.