OK, it's not exactly
a game, but it is kind of entertaining in a mindless way. It's pretty simple: the site gives you a word and you type in the first word that comes to mind. Then it gives you another word based on the word you just gave - the site is essentially learning word connections from the people who use the site. You can get stats on each word to see if you think the same way other people do or not. It's also kind of fun to come up with a word no one has entered yet - you end up stumping the computer, and it adds your word to its list.
It's a good time-waster. Link