Who keeps a separate log of thier car?

[Sapper]

After a mate of mine bought a car where the previous owner kept a log (incl all reciepts) of his car, I decided to do the same thing myself. Not the log in the service handbook, but a separate folder with everything i do to the car outside of Ford Scheduled Servicing.

Anyway, one if its many uses realised today as I was able to use a previous reciept to get the price I wanted for new rear tyres at a place that took some care of my car.

So I was wondering, who else keeps a record of what they've done with their car?