Robo-Pavoni ; learning to make espresso machine from scratch (via Make)
The design itself: take a Pavoni head, build an adaptor to connect to normal plumbing. Add a machined plate with water inlet (this is a plumb-in system), thermometer, and heater. Mount all in a brazed steel base.
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.