Since I'm a pretty avid runner, I love the ability to keep track of how much I run per day and what distances.  My brother of all people sent me the GMaps Pedometer which is based upon Google Maps which allows you to record your walking (or in my case, running) path with just a simple double click. 

 

It's by no means perfect, but it gives you a pretty good idea where you run and how far.  The line connector works in straight lines only, so if you run on a curvy road, good luck on getting it to be the exact match.  Below is an example of that:

 

 

On the left hand side, you can even turn on a calorie counter which you enter your weight and it will calculate based upon the distance recorded.  This just makes outdoor running that much more fun!