Dustin Diaz have a made a very impressive Tetris game using Yahoo! User Interface, a challenge for the faster coded Tetris game with the langage of their choice. Dustin have made his implementation in 2.5 days and didn't win the challenge, but really very well done. A very useful AJAX experience to see some of the usage of the YUI. I was a tetris addicted with my very first game boy, but for this AJAX-tetris I have some difficulties to use the keyboard.
Using a combination of the Event Utility and the DOM Collection utility, I was able to roll out perhaps the sweetest piece of eye candy I've ever built. And granted, it's not to say that it hasn't been done before, but with the help of YUI, this bad boy works in Firefox1.0+, Opera8+, Safari2, and IE6, and yes, it only took 2.5 days! Go ahead, see it in action!