I'm a big fan of pointless gadgets and big numbers, and someone called Daniel de Bruin has built a gadget that satisfies both those qualities.
To celebrate being a billion seconds old (just under 32 years old), Daniel built a gearing mechanism whereby the first gear would have to turn 1 googol times in order to turn the last gear just once. A googol is 1 with a hundred zeros after it and, as Daniel points out, that's a number bigger than the amount of atoms in the universe. A googol is also called ten duotrigintillion, ten thousand sexdecillion and ten sexdecilliard.
The gadget has 100 gears and each gear drives the next with a ratio of 10-1, which means a gear must turn 10 times before its subsequent gear turns once. Do that with 100 gears and you get your googol.
This particular gadget is just a prototype and it wouldn't run anywhere near long enough to turn the last gear once, but Daniel is going to create a version that could run for much longer. This proves he's completely bonkers, which is a quality I respect.