Monitor size and how far back do you sit?

I currently have 2 x 19" LCD monitors side by side. They're 1280x1024 (so not wide screen), and I'm having some issues imagining myself looking at six of them in 2 rows of 3 (my planned setup).

Right now, I sit about 2-4' from my monitors, and I'm thinking that I might have to move back a bit with my future setup. I'm building my own monitor mounts so I have a bit of flexibility there. Maybe I should build them to stand from the ground up instead of on the desktop.

So I have three questions:
How big are your monitors?
How do you arrange them?
How far back do you sit while playing?

Well, 19" is a bit big for 1280 x 1024, that is 17" resolution.

How big are your monitors? 30" and 17"
How do you arrange them? 30" turned vertical, 3 wide 2 high, flanked by 2 columns of 17", 3 high. I may upgrade these to 20.1".
How far back do you sit while playing? About 3 - 4'

i have heard the rule of thumb was:

optimal viewing distance from monitor == twice the diagonal

considering gamers like to immerse themselves in their game world, i would imagine most gamers are closer then 2 x diagonal