Common Denominators

What do Wiffle balls, bad alibis, donuts and bagels have in common? If you said they are things with holes in them, then you'll enjoy playing this game, in which house musician Jonathan Coulton asks contestants to name the common denominator in a list of four words.

Source: http://www.npr.org/2013/11/14/245040422/common-denominators?ft=1&f=1008

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