I like to keep a secondary checking account with enough money in it to pull from when I am traveling, but separate from my main finances in the event my account or card were compromised while I am traveling. So I went looking for an ATM card that charges no fees and does not have any international conversion fee.
Fortunately, I found exactly what I was looking for in a Charles Schwab checking account. We just came back from 3 weeks in France, and it worked great. I checked my withdrawals, and they were exactly what I expected at the normal conversion rate. And the few times I have called in with questions, etc, their customer service folks have been absolutely wonderful.
For those who want more than a back up account, this checking account is linked to a brokerage account that allows easy transfer of funds.
http://www.schwab.com/public/schwab/banking_lending/checking_account