The AdriX icon theme consists of beautiful icons for Gnome desktops. In this tutorial we will help you install it under a system running Ubuntu 11.10/12.04. Here are the icons used by AdriX:
AdriX Icon Theme Installation
Open the terminal and run the following commands to install and enable AdriX:
wget -O AdriX-gnome.tar.bz2 http://goo.gl/CjrTj
sudo tar jxvf AdriX-gnome.tar.bz2 -C /usr/share/icons/
gsettings set org.gnome.desktop.interface icon-theme 'AdriX-gnome'
Here are some screenshots of AdriX under Ubuntu 11.10 Oneiric Ocelot:
For more icon themes, check this page.