Well many of my friends had given GRE. Today while reading a post in one forum I stumbled across this link Number2. A user who posted this link quotes.

Well friends this is one awesome site that i stumbled upon very recently.It creates a seperate database of your study, sends you words that u master into ur mailbox, keeps track of ur progress and has got the A-Z of GRE and TOEFL .Best of ALL its FREE.Create your account and start using it.

I did visit the site though didnt register myself and check features. But am sure aspiring GRE, TOEFL students can give it a try.