The future was supposed to bring us some crazy things, such as underwater cities and 200-year lifespans. We're still waiting. Author Paul Milo discusses the ridiculous, bizarre, and just plain wrong predictions of the Twentieth Century in his book Your Flying Car Awaits: Robot Butlers, Lunar Vacations, and Other Dead-Wrong Predictions of the Twentieth Century (Harper Paperbacks, 2009).

What were you hoping for? Post your ode to that never-got-invented technology below!