Better video via the link I submitted a year ago:
<a href="http://news.ycombinator.com/item?id=468063" rel="nofollow">http://news.ycombinator.com/item?id=468063</a><p>This item has also shown up several times before:<p><a href="http://searchyc.com/shoelace" rel="nofollow">http://searchyc.com/shoelace</a><p>It's one of the methods I use to assess how to present things:<p><a href="http://news.ycombinator.com/item?id=1059659" rel="nofollow">http://news.ycombinator.com/item?id=1059659</a><p>It lets me know if someone will like puzzles for their own sake, or if "everything has to have a use."