Other
World Wide Words/exploring the English Language
"World Wide Words is devoted to the English language - its history, quirks, curiosities and evolution. The Words site is organized into sections, each with its own index to help you find your way about."
English Plus+
Quotation Marks With Slang: Rules for Use
This site discusses using quotation marks with slang and an example is included.
English Club
English Club: Learn English: Vocabulary: Word of the Day
Links to an idiom of the day, phrasal verb of the day, slang of the day, and saying of the day along with a sign up to have these sent via email each day.