Stumble Upon et al

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Stumbleupon.com currently aggregates videos from CollegeHumor, DailyMotion, FunnyOrDie, Google, MetaCafe, MySpace, Vimeo and YouTube.

As of June 13, 2010, sites using StumbleThru include BBC.com, Blogger, Break.com, CNN.com, Collegehumor, Flickr.com, FunnyorDie.com, Howstuffworks.com, HuffingtonPost.com, Metacafe.com, Pbs.org, PhysOrg, Rolling Stone, Scientific American, The Onion, Wikipedia, Wired.com, Wordpress, Youtube.com.

See also:

• Delicious (website)
• Digg
• Fark
• Reddit
• Slashdot
• bit.ly
• tinyURL
• Social bookmarking
• Web 2.0