How-To: A Working Paper Wrench:
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At Maker Faire Bay Area this year, Jay from MakerBlock found himself needing to tighten some wingnuts, but he didn't have a wrench. Rather than asking around, he hacked together a solution on his own. It's super simple: just one piece of paper. Roll it up into a tight tube and fold it in half. To use, place the paper tube around the wingnut, squeeze, and turn.
Read the full article on MAKE