If you've written any kind of validation on user input, like onkeypress then you'll know that sometimes you want to throttle the amount of times your function runs. A good example of this is Ajax based username validation - you don't want to hit the server on every key press, because most users will be able to write their name in around 1/10th of a second, so you should throttle the ajax request until the input is dormant for 100ms.
So with a bit of magic JavaScript making use of the ever useful closure JavaScript offers, we can create a simple method to handle this for us:
function debounce(fn, delay) {
var timer = null;
return function () {
var context = this, args = arguments;
clearTimeout(timer);
timer = setTimeout(function () {
