One of the best parts of Google Chrome is the theme. It’s simple and attractive. Now you can have that same theme (minus the top-window tab placement) in Firefox 3, thanks to a developer named “falconer”.
Download Chromifox, the Google Chrome theme for Firefox 3.
Update as of 2018-02-13: Extensions such as these are no longer supported by Firefox as it has moved to the new WebExtensions system. If you’re looking for alternatives to your favourite Firefox extensions take a look at this handy article from Digital.com.