Boggle is an interesting game and can be very educational. This version of the game allows you to play and compare your performance with the computer. The game uses the OSPD. You can lookup words based on online dictionaries and build wordlists.
Ack!words is a new word puzzle game that combines elements of Scrabble, Tetris, and Collapse to make a wonderfully addictive alternative to solitaire. Remove all of the letters from the board by finding words in any direction.