The Cube

Everybody wants to leave a mark on the internet, and almost nothing survives. So here is 9,234 cubes in nine layers around a Master Cube — buy one, put something of yourself on it, and it stays there forever.

A layer only opens once the one above it has sold out completely. The deeper it gets, the more it costs and the more you can leave behind — and the only way to see the inside is for the outside to fill up first. Nobody gets in alone.