Install Ambiance-Dark Gtk theme on Ubuntu 12.10/12.04/Linux Mint

Install Ambiance-Dark Gtk theme on Ubuntu 12.10 Quantal/Ubuntu 12.04 Precise/Linux Mint 13

Ambiance-Dark is modified theme version of original default Ubuntu theme, It looks much better than default ambiance theme with Malys-ex icons. This theme is for those who like dark themes and like to use on their desktops.

Theme tested on Ubuntu 12.10 with Gtk 3.6 and Ubuntu 12.04 with Gtk 3.4

Install Malys-Ex Icons or Check icons collection
Also Download Black Wallpapers
You can use Gnome-tweak-tool or Ubuntu-Tweak to change themes.

To install Ambiance-Dark theme on Ubuntu/Mint open Terminal (Press Ctrl+Alt+T) and copy the following commands in the Terminal:

Terminal Commands:
sudo add-apt-repository ppa:noobslab/themes
sudo apt-get update
sudo apt-get install ambiance-dark

That's it

Source: Ambiance Dark