As much as I think I'd like my cubicle to be tall enough to have a standing-height monitor (so, ~6'), I also have heard it's important to have line-of-sight to something "far" as in 20 feet or more away, and suspect that too-tall walls would also make it too dark.
This is a very interesting comment. I won't work open office (have found a new job specifically to get out of that environment) and all the cube jobs I've had over the years have had very high ceilings. I wonder what it would be like to work in a 6ft cube with only 8 ft ceilings, perhaps in a very tall skyscraper. I have a window cube right now and can see the sky from my chair, pretty nice and that takes care of the 20 foot rule...
