I have all of my components hidden under a stairwell and nothing is out in the open. I simply made a couple MS Paint documents and put it up on the wall beside my components.
For my power bars, I always know which component is plugged into which outlet. It's also great for my AV setup because I always know how everything is connected. Anytime I make a change, I just pop onto the computer and update the document and reprint. It's a clean setup that is easy to access.
The downside is that it only works on hidden components or racks. For components that are out in the open you would have to keep the document on your computer.
Just an option if you want something different.