Here is my little corner of the house. I actually remember pulling this thread up many moons ago when I was in the design phase - pretty much took a combination of the rails another poster used and the under bench reciever system.
I thought about the rails, but figured it would be a channel for everything to get caught in and I would constantly be cleaning. The problem with the under bench system is storage of tools you aren't using - the long tubes take up a lot of space.
So I have a modular system - every tool is on the same size block and can be moved to any location in the bench in any combination (with the exception of the Dillon swager). It gives me the flexibility of the rail system (almost) and the modularity of the under bench system.
Anyhoo, here is my bench - these pics were taken a while back, so it's already somewhat different. I still need to add storage shelving under about 3/4 of it and shelving above it as well to utilize some empty wall space. Not bad for only having part of the master closet.