I had been meaning to do this for a while, but I finally set up a Fuelly account today to track my mileage. 18.1MPG on today's fillup; it would have been better if it wasn't in the 20's recently. I figure it'll give me a good idea of my mileage long term, and seasonal variations. The app also makes it pretty convenient.
I'm trying to convince my dad to do it too, since he hand calculates his mileage at every fillup anyway. How many of y'all are using it?
I dont use Fuelly, but I do use a similar app called Fill up. Same premise other than i can export the data to use in excel or expense reports as well as they have multiple charts and time lines for quick reference to basic information.
I think any type of tracking like this a really good thing to get in the habit of.
I have been using a different app for the time the last 2 years and just started a fuelly account a couple of weeks ago and re-entered all the data I had from my other app as well. I like how on their page you can compare apples to apples so you can really see how your truck compares to others that are just like it.