Web Tweaks Essentials
5 Add-ons in this Collection
Greasemonkey by Anthony Lieuallen, Aaron Boodman, others
Restyle the web with Stylish, a user styles manager. Stylish lets you easily install themes and skins for Google, Facebook, YouTube, Orkut, and many, many other sites. You can even customize Firefox and other programs themselves.
Automatically find user scripts on Userscripts.org (requires Greasemonkey or Scriptish)
custom additions to Stylish extension (only works with Stylish v1.4.3, newer not supported)
I can't be bothered to change SC, so AMO will allow it to be uploaded
StyleSheet Chooser Plus (aka SSCP) persists choice of website stylesheets.