I presume most of you already use it, if not its pretty easy to install. Avant Windows Navigator (AWN) is a dock application (similar to the Mac dock) which happens to be the stablest dock I have tried. (The other popular docks include Cairo-Dock and GNOME Do, these are available from the Ubuntu Software Center)
Installation:
Go to GNOME Menu > Ubuntu Software Center, there search for AWN, install it. To start using it go to GNOME Menu > Accessories > Avant Windows Navigator.
Themes:
Now theme-ing the AWN is as important as getting it installed. Here are some themes (official AWN themes): AWN Themes
Download the ones you like. It will be in .tgz format. Now to install the theme, open the AWN Manager (it should be located on the dock itself) and then click on the ‘Themes’ tab. Click on the ‘Add’ icon and then locate that .tgz file you downloaded. It will be installed. Now to apply the theme and click ‘Apply’. The following screenshot should explain things:
Thats it!
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