Those Belgians really know how to pull off a prank. (There's a reason they were named one of the 12 coolest nationalities.)
See what happens when a TV program decides to serve Mobistar, a hated Belgian phone company (is there any other kind?) with a sample of their own customer service. They deposit a large steel container, a "customer service" number printed on the side, in front of the entrance to the company headquarters. Inside the container are—, well, watch the video, especially the final twist of the knife. (English captions, for the Flemish impaired.)
The Brits should try a similar tactic. I know a BT customer service rep I'd like to subject to that synthesizer.