What happened when you were faced with a sky-high veterinary bill?

We often hear people refer to their pets as members of the family, so it shouldn't come as a surprise that they're willing to do almost anything they can to keep their pet healthy. But as vets have more sophisticated diagnostic tools and expensive drugs the bills can create financial hardship. What's behind the costs and can something be done to make care more affordable?

Our question: What happened when you were faced with a sky-high veterinary bill? How did you deal with it?