Faenza

This icon theme for Gnome provides monochromatic icons for panels, toolbars and buttons and colourful squared icons for devices, applications, folder, files and Gnome menu items.

An installation script let you choose the logo of your favourite distribution and the appearance of the main menu icon (Gnome/distrib, monochrome/colour).

Several themes are included to fit with light or dark panels, menus and toolbars.

Installation
Download the tar.gz file and extract it. In the new folder created, run the ./INSTALL script to choose the distribution logo (Ubuntu, by default) and the Gnome menu icon. If run as root, the script will copy the iconsets to /usr/share/icons to made them available to all users. Some default icons used by Rhythmbox and Dockmanager may be also replaced.
Run ./UNINSTALL as root to restore defaults icons.

Launchpad PPA
Faenza icon theme is available to install via a PPA repository. Open a terminal and run :

    sudo add-apt-repository ppa:tiheum/equinox

    sudo apt-get update && sudo apt-get install faenza-icon-theme