I found Simon Willison’s lightningtimer.net Javascript timer to be totally awesome. The app is written in Javascript, all on one page. It lets you specify a time, and then a big-font timer counts down. The timer takes up the whole page. It can give you a warning, the background turns pink, when the timer is almost up. When the timer reaches zero, the background turns red and 0:00 blinks. Take a look at the page source for documentation on how to use lightningtimer.net. He says that he needed something for a Lightning Talk and this is the result.
Looking at the code (like I said, the Javascript is all in the page source, so just “view source” in your browser), it is a really cool example of Javascript. I was amazed how simple and elegant Simon’s code was. As someone who definitely is a poor Javascript hack, it is nice to see some good Javascript. And, I can use it as a tea timer too! 🙂