Thanks for the information Jamiel - the INSPASS sounds like an excellent idea.

At Heathrow there is a separate 'Fast Track' section of immigration, provided for travellers in Club World/First Class on BA. I presume that business travellers on other airlines are also offered the same facilities. It isn't automated like INSPASS, but there are far more immigration agents per traveller than in the regular immigration hall. This speeds things up enormously for non-EC-citizen business travellers.

Every time I fly into Boston there seem to be HUGE queues for non-US citizens, - the only way to get through immigration quickly is to rush off the plane and be at the front of the line!