This month the payment went out a couple days late, and we got whacked with a $39 late fee, cancellation of the promo 0% rate (setting it to 8.9%), and a $20 finance charge.
So, I called them up, listened to "Your call is important to us!" for ten minutes, and was quickly bounced to a second-level account rep.
Me: "I just got my bill. We had a late payment. I'd like to have my account reviewed and my promotional rate reinstated if possible."
Her: "Ok. I can review your account. [5 second pause.] I reviewed your account and we will restore the promotional rate, with the original terms, and expiring with the original date. This will take effect in two business days."
Me: [blink blink] "Thank you very much!"
Her: "And I cancelled the $39 late fee. Anything else we can help you with today?"