Duracell CPU Load Monitor

I'm going to have to try to build one of these. This website has details of how to build a linux CPU load monitor using a Duracell battery tester.

The battery has a small tester that shows the charge left in it when two white dots are pressed. This shows up as a little bar graph. It works by using a layer of conductive ink that heats up when an electrical current passes through it. Used with a thermally-activated dye, this can be used to build up a basic bar graph.

This is just the kind of geek gimic that appeals to me.