I placed an online order this morning with a well known retailer in Guildford, value of approximately 90 quid, and had to provide the secret number from an SMS to allow it to go through. Had to go and find my phone (I never use it and it is generally switched off in a desk drawer) as I was making the order via computer. I'm in favour of increased card security if it keeps our money safe but I do wonder how/if the banks will find a way to monetize this 'service' to their benefit and our cost.