I've been using 4 23inch monitors in an inverted T layout for years now. I slowly scrounged up a matching set as other engineers upgraded their monitors. Its nice to have one monitor just for email and crud out of the way of 'real work'. I even have another 19in monitor off to the side just for the console of my Linux dev box, but I usually use X forwarding to access it from the main workstation.
Yeah, I could probably be talked in to trading all these for a 39in high resolution setup. But I'm pretty happy with this setup, and I can angle the sides in for a better viewing angle. And this was a pretty cost effective setup.