For all those wondering why this subject suddenly returned to the limelight, it's due to a paper realased today in the Proceedings of the National Academy of Sciences (or pnas for those in the know)
I think it's because Mozilla 1.1 was released yesterday and uses Gecko... That's a bit more geeky:)
Use a cordless door bell. With a different chime to the actual door bell - otherwise hubby will be anwering the door while wife suffers..