A more sensible typing speed tester
When I became interested in my typing speed, I found a handful of Javascript-based typing speed tests that had a built-in penalty. Generally, you had to click a Start button to start the timer, which meant that one hand was on the mouse before beginning. Some even required clicking Stop afterwards, which meant another trip to the mouse. Being interested in my typing speed, not my hand-to-mouse speed, I decided to write my own test.
As this has been written solely for my own use, it is only really tested in Firefox. If you're experiencing difficulty with some other browser, this may be the reason. Also, since I am lazy, this simply measures the number of characters in the box when you're done. So you could cheat by pasting something big.
The timer starts when you start typing, and stops at the last character you typed, so it doesn't count the time needed to click the button (or to TAB to it and hit SPACE).