I love the NatWest
I once had a standing order set up, transferring money from my Sister's account to my savings account.
I got a letter one day, stating something to the effect of "There is not enough money in your account, to transfer from your sisters account to yours. We have charged you £25"
I went into the bank and asked them to explain. They read it, then re-read it a few times with a confused expression, then said it was clearly a mistake and they'd sort it out.
A few days later, my Sister got a letter: "There is not enough money in your Brother's account, to transfer from your account to your Brother's account. £25 - ker-ching"
Mind you, I still bank with them...