Introducing XUL - The 'Net's Biggest Secret: Part 2

As the last example demonstrated, using XUL, you can give your site's visitors a unique experience by modifying the browser to make navigation faster and easier. And, when you start throwing JavaScript into this mix, all sorts of powerful new opportunities arise. Here's a simple example, which displays a search box that’s always visible. It also demonstrates the potential for building forms with XUL.

http://www.sitepoint.com/article/xul-nets-biggest-secret-2