Here's a quick mock-up of what I was talking about in the previous post. It's an overhead image showing a possible marching formation in a 10' wide corridor. I just whipped this up in Google Sketchup using the first appropriate image I could find in the 3d Warehouse, then modified the image moderately in the Gimp.
For the actual diagram, I would need to do my own figures, make each different, and position them more exactly, possibly with some goblins added. There'd probably be some kind of tic-tac-toe grid centered on the lead fighter so that I could number the boxes for possible use with dice rolls of some kind: overhead bomb hit location, splatter effects, or the like. Not that any of these dice rolls will be that complex; I just think that when you get to something really simple like compass directions, it's easier to explain it with a diagram.
But, as mentioned previously, the main goal of this diagram is as a reminder of how much room a figure actually takes up, and how long a weapon can actually reach. Perhaps I should do a long corridor with multiple figures, to show people carrying 10' poles or other gear.