I'd like to extend the height of our cubes with panels that mount on the top of the walls. This would add privacy, decrease noise, and cut down on the non-stop greetings people who stand at their desk have to give everyone who walks by.

Any of these would do - departments could even decide on their own color!

http://www.staples.com/cubicle+mount/directory_cubicle+mount?rpp=18&pn=1&sr=true