LittleGreyCat: One thing that puzzles me - if you are on pre-pay and go over your limit how do they charge you the daily rate?

Does this assume that you still have money in your account as would be the case if you have mixed voice and data from the same account?
i.e. using a smart phone to do voice and data.

If you are using a 'dongle' (as I am) surely you would pay, say, $30 into your account, convert it to a data add on then have no money in your account for voice calls or for paying an ad-hoc daily rate.

Cheers

LGC