Elenco Electronics's "Telephone Bug Kit" (soldering required) gives your kids everything they need to build a dime-sized wiretapping device that lets them listen in on your phone conversations. Educational and creepy! Link (Thanks, Tyre!)
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.