Majority of modern browsers (or rather rendering engines) already support very useful DOMContentLoaded event which is being fired right after HTML content finishes loading. These engines are:
- Gecko version 1.8+ (Firefox 1.5+)
- Webkit build 500+ (Safari 3+, Google Chrome)
- Presto version 9+ (Opera 9+)
You can test if your browser is supported here: http://perfectionlabs.com/quicks/advanced-javascript/DOMContentLoaded/.
There is no native support for DOMContentLoaded in Internet Explorer, but it can be hacked by running custom scripts found around the internet, for example with one like this: http://www.hedgerwow.com/360/dhtml/ie-dom-ondocumentready.html, or via virtually any of popular JavaScript libraries like MooTools, jQuery, or Prototype.