document updated 15 years ago, on Nov 23, 2008
http://www.stirrdup.com/
Has "passive voting", where commenting (and other actions) upvote a story. No downvoting, though this means "controversial" stories are promoted, rather than more accurate stories. Homepage sorted by time.
http://www.dzone.com/
Software development
Thoof http://www.boingboing.net/2007/06/27/thoof_social_bookmar.html
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