Quick tip: Changing menubar icons
One of the more notable graphical changes in Leopard was the change of the Mac OS menubar’s style into a translucent white and changing icons from color to a black and white style. (With the exception of the international menu.)

However sadly some developers of third party apps have seemed to ignored this fact and their menu-apps are still playfully colorful. It’s not a terrible mistake but it always irks me. Bizarrely the HIG is silent about this issue.
Fortunately there is an easy fix for this problem. Simply go to the relevant application, right-click on it and choose “Show package contents”.

The locate the menubar icon. This will typically be a png in Contents/Resources. Now simply edit it in your favorite image editor. Then simply restart the app with the icon.