Many people have discovered free information, such as Wikipedia. Wikipedia is free as in beer, and free as in freedom - you can do whatever you want with the data (as long as you don't restrict other people in the process). I like free data, so does the US government. Everything that the US government publishes is free. That's not the case with the UK government.
Encumbered Post Codes
While doing some work for the Open Street Map I noticed a link to the Free the Postcode project. Postcodes aren't free, that's not nice, people want my postcode all of the time (banks, on-line shops, insurance companies etc). The Royal Mail owns the postcode data, and you can buy a copy (but even if you buy a copy, you can't redistribute it - buying isn't the same as owning).
In an ideal world, I'd like to use only free (as in freedom) data, so I'd like to stop using postcodes. Perhaps not very practical. Post codes are slightly free (as in beer), you can look up a post code on the Royal Mail web site, but there are terms and conditions (aren't there always!)
One of the conditions is :
The Postcode/Address Finder service may be used for non-commercial personal use only. ... You also may not extract, copy, reproduce, re-utilise, publish or distribute any part of the data you obtain using the Postcode/Address Finder service in any material form (including photocopying or storing it in any electronic form) or use it in any way that is not expressly permitted by these terms and conditions.
So, there's two more reasons why I shouldn't give shops my post code - I would be breaking the terms and conditions!
The Royal Mail want their cake and eat it. They want to own, and tightly control postcode data, and they also want everybody to use postcodes. Just say "NO".