Although the Mac OS X default look is clean and polished, sometimes I feel that it could be better. Fortunately, there are several ways to customize and refine your OS X appearance, including the dock.
IconPaper has a beautiful gallery of dock themes, icons, wallpapers and other tweaks for your Mac. You can find some great stuff at DeviantART too.
To change the theme and icons of the Mac OS X dock, you will need CandyBar or IconBox. To add spaces to separate groups of applications in the dock, you can use the free application SuperDocker.
The dock theme used in the above picture is Obsidian, one of my favorites.
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