Google Knol
The "Wikipedia killer." Wikipedia did not notice.
CAUSE OF DEATH: Got about 175,000 views a month. Wikipedia does that before breakfast.
Google announced Knol on December 13, 2007 as a place where people would write articles under their own names and collect ad money. It was often viewed as a rival to Wikipedia. A Google product manager insisted the matching font was "simply a coincidence." By mid-2009 the whole site was getting about 175,000 views a month. The profit-sharing was criticized for inviting self-promotion and spam. When Google announced the end in November 2011, a TechCrunch writer said it was a surprise "because I figured Google had already shut it down." All content was deleted after October 1, 2012. Its Wikipedia page is doing fine.