Control iMac and LED Cinema Display Brightness Simultaneously I have a iMac 27'' and a LED Cinema Display 27'' connected to it. And I've noticed that to be able to control brightness I need to open the Display.prefPanel  and modify the brightness of the displays individualy.

Is there a way to do this SIMULTANEOUSLY? Maybe with a third party app? If not, is there a way to assign a keyboard shortcut to the second display brightness?
I just started using Dimmer Than Dim, a free app in the App Store. I only have one display (iMac), however.