http://en.wikipedia.org/wiki/List_of_faux_pas
Highlighting specific examples is left as an exercise to the reader.
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Alphax -
http://en.wikipedia.org/wiki/User:Alphax
Contributor to Wikipedia, the Free Encyclopedia
"We make the internet not suck" - Jimbo Wales
Public key:
http://en.wikipedia.org/wiki/User:Alphax/OpenPGP