http://www.popsci.com/bacon Bacon can be used to cut steel.
http://people.umass.edu/klement/tlp/ Wittgenstein's Tractatus Logico-Philosophicus has been typeset in LaTeX.
http://www.mnxsolutions.com/security/two-factor-ssh-with-google-authenticator.html Google's new two-factor authentication can be hooked into PAM.
http://blog.nyaruka.com/skypes-crazy-regex-easter-egg You can use sed-like regular expression replacement in Skype chats!
http://my.ilstu.edu/~jrcarter/ice/diurnal/extrude/ Forming tiny ribbons of ice by freezing water in pipes with a slit in them.
http://www.visual6502.org/JSSim/index.html This is a 6502 CPU simulated at the transistor level in your browser!
http://en.wikipedia.org/wiki/Pixel_art_scaling_algorithms Multiple algorithms are available to upsample pixel art (frequently found in old video games). Wikipedia's article compares several algorithms and shows some impressive results. This paper was also recently released and also gives excellent results. The supplementary material link lets you visually compare different algorithms.
http://www.flickr.com/photos/pepa_quin/3652206565/in/set-72157613753398532/ Lego reproductions of Starcraft units.
http://www.boingboing.net/2009/09/23/lamp-that-runs-on-hu.html This lamp uses a drop of blood to power itself.
http://www.dealextreme.com/p/mini-tritium-glowring-keychain-10-year-green-glow-6830 A keychain with a sample of radioactive material so it can glow in the dark.
http://en.wikipedia.org/wiki/The_Ashley_Book_of_Knots The book on knots.
http://www.sandwichproject.co.uk/ Help create the world's largest database of sandwiches.
http://www.netsoc.tcd.ie/~mu/wiki/ This website shows the shortest path between any two Wikipedia pages.
Gil's LotD (Link of the Day) publishes a link to a web page every day. The linked pages are chosen for their interesting, informative or entertaining content. You can read Gil's LotD on the web or in a daily email.
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