The self-described Crazy Russian Hacker of Youtube demonstrates in eye-watering detail a method for tool-free can opening: just grind down the can's rim on a handy block of concrete, then squeeze. The stunt is repeated several times, just to be sure you've absorbed the technique in all its complexity. It's all framed in post-apocalyptic terms, naturally: a kind of Russo-Survivalist Youtube version of Three Men in a Boat.
Opening a can without any tools
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.