My "stylish" minimal Firefox 4 theme advenced with addon by SpewBoy called Stratiform.
Stylish - [link]
(you need it for theme)
Theme you can download on [link]
For effect us is in screenshot you need 2 addons.
Stratiform - [link]
Omnibar - [link]
and if you want bookmarks buttons on right of screenshot download:
Google shortcuts - [link]
Enjoy this theme
03/14/2012 - Fixed transparent about:blank, compatible for Stratiform 2.1.1
01/22/2012 - Updated for Stratiform 2.0.1 and newer
05/29/2011 - Updated for Stratiform 1.2b and no need for Movable Firefox Button addon
03/29/2011 - Added transparent about:blank
03/24/2011 - Fixed addon bar