Naomi Wolf provides a chilling account of how Washington Mutual responded when she discovered fraud occuring in her account. The main take away, besides disgust, is that if you discover unauthorized transactions occuring in your account, close it immediately, no matter what the bank tell you to do.

As a side note, under US law, banks have a fiduciary responsability to their depositors.  The fact that they can get away with treating customers this poorly should give pause to those who believe that a fiduciary duty for brokers will be a panacea for bad behavior (it will not).