Post Office card
The UK Post Office also do a no comission on foreign purchases card but I haven't tried withdrawing money on it yet. Credit limits tend to be low though which may be a good thing for theft purposes.
I've used my Nationwide card in diverse places including small towns in India, Malaysia and the Carribean and never had any problems in getting cash in ATMs which are much more widespread than the brances of any particular bank.
The additional benefit of these cards is that the money is exchanged on the wholesale rate which is better than the over the counter tourist rate.
If the card is stolen you can cancel it - just take the emergency number or look it up on t'inernet.
One thing that I would do from now on is make sure I take two cards, each administered by a different clearing company. I was in France over the weekend when Visa had a server go down (I called the issuing bank helpline to find out what had happened) which meant that my (and all other) Visa card was declined. The Mastercard was fine though.