The easiest things to measure are how fast and how far you have ridden. To me that's nice to know but it's not how I define myself.

I want a meter that gauges how much fun I'm having. If I had such a device I suspect that, while it might take a serious speed push or hill climb to peg the meter one day, I might have to slow down or completely stop and talk with more people to max out my fun meter on the next.