MacAppStuff Trip
Lets you determine various motoring costs, such as the cost of a journey, your average MPG, how much fuel would be needed for a journey, and how much fuel you get for your money. It can also perform conversions between popular motoring values (MPH to KPH, for example).
The application will help you work out:
How much a journey will actually cost.
Your real-life MPG.
How much fuel you will need for a given journey.
How many gallons/litres you will get for a given amount of money
Other features include:
Load and save data to file
Copy input data and results to the clipboard
Launch Mac OS X's Calculator application
Use Imperial or Metric calculations for measurements in gallons/litres
Perform various motoring related conversions.