riahon: On a serious note - if any of you have a direct debit in place with TCL I would be ensuring that they have cancelled any pending amounts as a result of this error.
TinyTim: Mine was only 2.5GB, but an we normally only burn through 300-500MB/month it was enough to make me go home at lunchtime and look for war drivers!
jpollock: We have a new winner! Well done dm2000!
I believe it's 2gigabytes/block, at 2.95/block.
nzealander: As per my last reply, it is only the usage meter that is screwed up, nothing to do with billing, so I wouldnt worry about that part.