As an ex corporate pilot, I'm surprised no one has mentioned the DH125. In one or another of its guises it's still being produced, nearly 50 years after it's introduction - albeit by Beech.
The rudder bias system was invented, or at least perfected, at RAE Farnborough I believe. Every pilot who has flown an aircraft equipped with said system should get down on his knees and kiss the behind of the inventor.
