Sitting at my work bench working on freight cars I am thinking
My OCD doesn't actually like color-coded tools, since they then get mixed up too randomly and the paint gets worn and yucky-looking (VBG!)
I've found over the years that I rely on about four hand tool for 70% of my modeling, and about another dozen for another 25%, rarely dragging out the exotics and only using the powered tools (Dremel, soldering equipment, etc) when I have the opportunity and time to work on metal steam. Since my primary tool list is so small I keep a simple Plano tacklebox insert as my "tool box". Something like this:
It's simple, latchable, easily transported, and has enough slots in it to have one for files, pliers, "sharps", drills, etc. In fact, since I've moved four times in the past twelve years I've basically taught myself to "portable-ize" ALL of my hobby supplies, and I may have the world's largest collection of Plano boxes.
The nicest thing about keeping things organized like this is that it's really easy to pick up and bring a small prohect with me if I'm on the road, or if it's an especially nice day and I feel like working on the deck.