5 Interesting Materials, with unusual properties. The site includes links to more information and videos:

1. Dilatants - fluids that get more solid when stressed.
2. Auxetic materials - materials that get thicker when stretched. Pull them in one direction and they expand in another.
3. Superfluids - liquids that flow without friction. They can effortlessly flow through the tiniest of cracks and will even flow up the walls of a beaker and out the top. It's possible because all the atoms in a superfluid are in the same quantum state, so they all have the same momentum and move together.
4. Ferrofluids - magnetic fluids that can look spectacular. They're made from nanoscale magnetic particles suspended in a liquid.
5. Dry ice.

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