Ambiance and Radiance Evolved
Modified versions of Ubuntu's default themes...
Installation on Ubuntu 11.10
Type the following on a terminal:
sudo add-apt-repository ppa:victored/light-themes-
sudo apt-get update
sudo apt-get dist-upgrade
Installation on Ubuntu 11.04 (Unity Only)
sudo add-apt-repository ppa:victored/ambiance-
Now open the Update Manager, click on Check and then Install Updates
IMPORTANT: This will upgrade your current light-themes (Ambiance and Radiance) package, so you won't be able to use the default themes anymore (unless you uninstall the themes - see below). You'll get all the required packages from there
THE REQUIRED ICON THEME IS PROVIDED THROUGH THE PPA
Please remove any previous version of the Ambiance and/or Radiance theme under your ~./themes folder
Installation on Ubuntu 10.10 and 11.04 (Classic session)
Add the theme's PPA. Just type the following on a terminal:
sudo add-apt-repository ppa:victored/ambiance-
Now install the themes:
sudo apt-get update
sudo apt-get install light-themes-evolution-classic
IMPORTANT: You can use this version alongside Ubuntu's default light themes. If you added the PPA earlier and upgraded the light themes on Ubuntu 10.10, please follow the instructions above and then downgrade the light-themes package...
Uninstalling the themes
UNITY VERSION (Ubuntu 11.04)
If for some reason you need to remove these themes, you can revert the changes [made by this PPA] typing the following on a terminal (CRTL+Alt+T):
sudo apt-get install ppa-purge
sudo ppa-purge ppa:victored/ambiance-
After that, you'll system will be as it was before
Source: http://www.webupd8.org/2011/12/light-themes-evolved-ambiance-and.html