These are all great ideas!  A lot of things I didn't think of that I can totally see would be very useful and handy to have along!  I'm working on two projects with this (primarily #2):
1.  a suitcase of sorts with custom padded slots for everything (probably a lot like what Mark mentioned) for use when traveling.
2.  a mobile "command center" for the back of an SUV

I don't want this thing to look like I took a pre-fab computer desk and threw it in the back of my SUV; I'm having custom blueprints drawn up and the materials for the modifications will be the same as the interior materials and colors.  It's going to look like it belongs there.  It's going to serve multiple purposes, one of which will be to aid in spotting.  I'm an avid road-tripper and as such, I have lots of equipment, spare parts, etc. that I have found I often need--this is going to help that be more orderly as well.  This project is the culmination of a couple years of brainstorming that I'm finally going to do and I'm quite excited about.  The blueprints are currently being drawn up and I've made arrangements for the modifications to be built, so plan on a debut (with pictures!) in the next month or two!  Obviously, it will be a work-in-progress and I don't want to rush it too much because I want to make sure it's exactly what I want and exactly what will work for me.

My only concern is what may happen when the occasional law enforcement officer stops by to inquire what I'm doing and sees this whole set-up in my car!  That's sure to be a bit more difficult to convince him or her that it's nothing more than a harmless photo-shoot!