Some of you might already know this trick but I have just seen it for the first time on an Audi forum and it worked on my scirocco.
If like me you have the manual dual climate control and get fed up of turning both knobs up and down to the right temperature you can now adjust them both simultaneously just by turning one knob.
Turn the ignition on but don't start the engine and have ac turned on. Hold the auto button on the right ac knob for 4 seconds. When you turn the drivers side knob the passenger side temperature will now move at the same time.