Here’s a cool DIY showing you how to make a force sensitive resistor for about $6-$20.
It’s a great way to build something that needs to sense “force” of something such as your hand strength, leg strength, etc…etc… In other words, you could build a soccer game machine with it.

Other interesting stuff at Zedomax.com: DIY, game machine, hand strength, leg strength, resistor, soccer game
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