Many large banks will charge you at least $2 when you use another bank's ATM. That's on top of the charge that the ATM owner charges you. There are many ways you can avoid these fees as described in this CNNMoney.com article, Hate ATM fees? Try these fee-friendly banks
One thing that wasn't mentioned is reward checking accounts. In addition to high interest rates, you're also rewarded with ATM fee reimbursements. Of course, you have to meet the monthly requirements.
The author of this other CNNMoney.com article
has an interesting story of how she was able to avoid ATM fees with her old banks which included NetBank and WaMu. Both of these went under. Now she's content on using two banks: Chase (kept free with direct deposit) and Charles Schwab Bank.