Windows 7 Taskbar Color Changer is a free portable tool that allows you to change your Windows 7 taskbar color with one click without changing the color of your window borders and start menu.
How to use:
Run the tool. (You might have to wait for several minutes)
Click on the rectangle to choose a color or click on Random to choose a random color.
Now your taskbar's color will be changed to the color that you selected.
(Requires .NET Framework 4)