A Google recruiter, while doing his spiel, told me in a light-hearted, offhand manner that some engineers call it "120% time". Having lurked here long enough and read similar sentiments from ex- and current google employees, it wasn't really news to me, but I was pleasantly surprised at his candor.
But do any of the other companies listed do 20% time? AFAIK, they only have infrequent "hack days".
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