Short of keeping a pen, paper, and notebook in your glove compartment, there's not really an easy way to track your driving habits between gas fill-ups. Enter MyMileMarker, a simple and useful solution for figuring out how much driving is costing you in gas, and how many miles you're likely to put on your vehicle in the course of a year. Best of all, you can upload your data to the service for free on the Web, or using your mobile phone.
Setting up your vehicle with MyMileMarker is about as simple as it gets--just put in the make and model of your car, or give it a nickname (useful if you're the type of person who names their car). Then, just give it a base odometer listing and your latest fill-up, and you're good to go. From there, you need simply add your odometer reading every time you add gas to your car, be it a fill-up or just a few gallons.
Here's where the mobile aspect comes in. Instead of using their own mobile service (like a call center or an automated message process), MyMileMarker uses Twitter as their medium for users to send in mileage reports from their phones. Users just need a Twitter account, and to befriend "Mymm." Sending a private message to that user with your mileage will automatically update your records and place the timestamp in for you.
Once you've provided MyMileMarker with three reports, it will begin to crunch your usage statistics. The more you use the service, the better the predictions get. If you miss a few fill ups, the service will do its best to calculate your laziness, and take it into account for the annual forecast.
There are a few missing features I'd like to see added. One is an option to call in your stats using an 800-number, since you're often times busy enough while pumping gas to sit and type. Another is the option to edit past entries. You can only edit or delete your most recent entry, which means if you mistype the price of gas, or your odometer reading, you have to delete, and then re-enter the listing (which you can only do from the Web).
Of course there are several other ways to track your gas usage--like getting a credit card just for gas purchases, and doing monthly odometer tracking on a spreadsheet-- but if you'd like the added benefit of predictions, MyMileMarker shows how scarily expensive owning a vehicle can be. For another take on the service, check out SolutionWatch's hands-on with it last month.