TED Magic Show: "There is a big metal spike under one of the cups.  After we both blindly shuffled the cups, he asked me to pick two random cups… and he crushed them with my hand." Keith Barry presents a magic trick at TED conference in 2004.
<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/44124348109@N01">Steve Jurvetson</a> from Menlo Park, USA
CC BY 2.0
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