Dominos (Not the pizza place with the cool delivery scooter - the little rectangular blocks). I hear there is a game that you play with them, but I think they are best known for lining them up in a row and then tipping the first one so that they fall like... well... dominos. The world record is apparently over 33,000 dominos in a single spiral.
Dominos are also used to make pool shots.
It turns out however that there are a lot of other things that will fall over like dominos when lined up properly. For example, how about human's tied to mattresses?
Or how about shot glasses?
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