Having switched to a capped gas supplier six months back, I was surprised
to get a 'Notice of High Bill' letter from them - especially since I have
given them 'real' meter readings every time.

It turned out on investigation that their meter reader had been round and
read the initial '0' as a '1' - adding 10,000 cubic thingies to the total.

Based on how many we actually used, I estimate that would have been an
extra £30,000 for this quarter. I'm quite glad they have a sanity check
built in to their system!