Imp was a small rear-engined car produced by the Rootes Group
between 1963 and 1976.
A direct rival to the Mini, the Imp was a revolutionary design, with an 875 cc all-alloy engine (which was later increased to 998 cc), all-round independant suspension, and a pneumatic accelerator.
Unfortunately teething problems with the car (due to inexperienced workforce, and a rushed deadline), coupled with some unconventional features (such as the above-mentioned accelerator), and cooling problems saw the reputation of the car damaged early.
This did not stop the car having a huge success in the European Rally circuit.
There are many imp enthusiasts all over the world, and they are still regularly competing in various rallies and racing events.
There is a yellow Imp in the Motor museum at Coventry, but it's a rusty piece of crap.