For those of you using Windows 7 or Windows Vista, you probably have already noticed that by default, Firefox does not have the cool glass effect that some of your other programs might have. You can make Firefox a little more transparent though, with the Glasser add-on.
Now, I’ll be honest – I didn’t think it would make that much of a change for me. Sure, some more of Firefox is transparent – so what? However, after giving this add-on a try finally, I might decide to keep it. I like the fact that it gives the bookmarks toolbar a little ‘bit more highlight and makes it stand out a ‘bit more too.
Overall, I think it does make the Firefox 3.5/3.6 interface a lot sleeker. You can pickup this interface changing extension from the Firefox Add-ons website.
The best Firefox UI tweak. Period.
These isnt any for Mac. :(