Keep Track of your Business Miles Automatically

I drive a company car.  At the end of the year our controller comes and asks how many miles I have on my vehicle and how many were spent on personal miles and how many were business miles.  I then have to go dig through my glove compartment, my desk and use google maps to recreate the last year of driving.  I would be great if I could just sit down in the driver seat and have my car ask me before I start driving "Are these personal miles or business miles?" and keep track of both independently for the entire year.