Vocab Quizzes

Long word lists with the same letters (abase, abash , aba......) can be such a bore. Vocab quizzes combine the randomness of the test, while maintaining a certain amount of order in your preparation. 

Here are a few good sites that I came across:

http://www.sheppardsoftware.com/vocabmania.htm

http://www.english-test.net/gre/

http://www.soundkeepers.com/GRE/