Want to make sure you back something up indefinitely? Then you could do worse than a digital data storage technique that uses laser light to store 360 terabytes of information on nanostructured quartz for up to 14 billion years.
I've always enjoyed water-distribution puzzles. They are simple in structure and usually straightforwardly posed, but their plain presentation belies their challenging nature. Here are three classic variations on the theme to wrap your head around.
Almost two millennia before the rest of humanity entered the industrial age, the Greek inventor Hero invented the steam engine, wind-powered machinery, and theories of light that couldn't be improved for centuries. And then he invented some really crazy stuff.