Test your word power! You can take the quiz over and over. Boost your score by answering quickly.
Build your vocabulary and impress your friends: Word of the Day
Show everyone how hip & cool you are: New Words and Slang (This is NOT Urban Dictionary, but I do like that one too...)
This thesaurus site only has a 2 week free trial, then ya gotta cough up the dough, but it's a cool word map: Visual Thesaurus . Similar to this one - and FREE - is Visuwords.
Bore the Hell out of everyone you know by giving them long-winded & pompous oral dissertations on the roots of the big words they ask you to define for them: Etymology