There appear to be a number of tools available that monitor the distance your mouse travels in a day,
I'm looking for one where I can trace a route on a map, and it tells me the distance between those two points.
This could be in arbitrary units for comparison, but better if it can take the map scale as an input to give actual distance.
Update, from @Ryans answer I did discover this,
To measure distances using Google Maps, click the “My Maps” tab on Google Maps website and select the “Distance Measurement Tool” - now select any two points on the map with your mouse and the distance will appear in miles (or kilometers).
Google Maps uses straight lines to calculate the shortest distance but if you are looking for more accurate numbers, trace the complete route by clicking at all the curves and deviations.
Still looking for same tool without having to mouse click multiple times.