Remember Watson? We're currently at IBM's offices watching the world's best Jeopardy-bot take on Ken Jennings, the winningest human to play the game. Follow @PopSci on Twitter right now for the live blow-by-blow, and stay tuned for a full report later today.
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.