A domino can knock over another domino about 1.5x larger than itself. A chain of dominos of increasing size makes a kind of mechanical chain reaction that starts with a tiny push and knocks down an impressively large domino. Original idea by Lorne Whitehead, American Journal of Physics, Vol. 51, page 182 (1983). See http://arxiv.org/abs/physics/0401018 and http://arxiv.org/abs/1301.0615 for so
![Domino Chain Reaction (geometric growth in action)](https://cdn-ak-scissors.b.st-hatena.com/image/square/580318f98ab62ff5c6576339557612835d3e27c8/height=288;version=1;width=512/https%3A%2F%2Fi.ytimg.com%2Fvi%2Fy97rBdSYbkg%2Fhqdefault.jpg)