I found this program a while ago and found that it does a good job doing what it should. Docker is a simple dock customization application. You can change the color of the dock, the dock style and several other little features that I haven't really looked into a lot. The only real modification I made was to change my dock to a black one which I think looks much nicer than the default.
My current customized dock:
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The main customization screen of Docker:
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You can download Docker from their site:Blocksoft - Shareware and Donationware for Mac and PC