A while ago, I wrote a web site named Healthwhere (I announced version 1 here about a month or so ago). It used ErnestMarples.com as one source of postcode data.
A few days ago, Ernest Marples disabled their service after getting a cease & desist letter from the Royal Mail. There's been quite a bit of press coverage about it (the BBC, the Guardian, the Register & Computer Weekly have all covered it).
Healthwhere has had a lot of hits over the last few days - there were more searches yesterday than during the whole of September. I figured that was because the stories linked to Ernest Marples, and Ernest Marples has a link to Healthwhere. Today, I realised the BBC story has a direct link to Healthwhere (in the "Related Internet Links", to the right of the main story).
Luckily, Healthwhere also uses postcode data from NPE, Free the Postcode and Dracos, so all the extra visitors have still been able to use the site.