Jim is 100% right here.  I am surprised that no bank is there yet.  I know of one in the works, that plans to be live this year.

Analysis Financial institutions should consider using a similar approach on their websites, either programming the function themselves or outsourcing it to Bank-Anywhere.com or others. Not only is it easier to use, the Ajax-based map looks more sophisticated and up-to-date. It’s important to make a good impression with locator tools since it’s one of the first things a prospective new customer will look at when considering opening an account at your bank.

Source: NetBanker 2.0: Bank-Anywhere.com launches branch locator mashup