Heard about this on the radio... Free Rice. For every word you get right they "donate 10 grains of rice through the United Nations to help end world hunger."
Or so they say... but I like word games and it's a nice thought...
Plus when I went to Dictionary.com to look up inveigle, I saw their word of the day is woolgathering and I had no idea it could also mean "indulgence in idle fancies and in daydreaming; absentmindedness." So it's educational.