This 2010 video demonstrates the wonderful and intriguing behavior exhibited by water when it is dripped on paper that is coated with "superhydrophobic" aerogel powder. The water forms tiny marbles and races around like it's on a griddle. This looks like it would be a lot of fun to try in person, possibly with some small people in attendance.
I write books. My latest is a YA science fiction novel called Homeland (it's the sequel to Little Brother). More books: Rapture of the Nerds (a novel, with Charlie Stross); With a Little Help (short stories); and The Great Big Beautiful Tomorrow (novella and nonfic). I speak all over the place and I tweet and tumble, too.