languagehat—Languagehat.com

Certainly one of the first MeFi user sites I read with any regularity, languagehat's (User #14752) blog is also one of the best. It's difficult to describe just how broad and deep are his interests and knowledge. Just today on the front page are entries about an old Scottish dialect still spoken by only two people in the world, several glosses on entries at the wonderful Polyglot Vegetarian language blog, a matching game using proper names and pinyin, and a speculation on the etymology of the word Moscow (in which lh correctly corrects the OED!). My favorite of languagehat's entries is still his demolition of David Foster Wallace for DFW's snooty idiocy about English usage.

And let me not stop there. His sidebar is filled with links to the cream of the website crop. Everything there is well worth a visit.