The dilemma: we run up a large bill each month with the various search engine PPC programs. Those bills can only be paid by credit card, due to the policies of the search engines. Our high-credit-limit card was disappearing and the only replacement card we could use had a much lower credit limit.
The first approach: I called the search engines and tried to get them to switch us to prepaying or invoicing or bank transfers. After many phone calls, applications, negotiations, and pleadings -- nothing.
The brilliant second approach: one of our accountants suggested prepaying the credit card directly, establishing a positive balance there. Then we run as normal, and instead of running up a big negative, we just run our card down to a zero balance.
I can't use the phrase "out-of-the-box" without wanting to kill myself, so I'll just say that was a clever solution to the problem. I hope to keep that idea somewhere in the back of my brain so next time something like this comes up, I can use it again. I love it.