And often it's simply about building and registering more cars – occasionally it's about allowing designers or engineers off the leash to come up with something truly special.

Whatever the reasons behind the thousands of special edition cars produced over the years (and that's just the Mazda MX-5 and Fiat 500 combined), we've picked 25 limited-run cars that show the highs and lows of the special edition. We'll leave you to work out where on the spectrum each car sits... We'll also tell you, where possible, how many survive on our roads today.