I wish I had gotten pet insurance a few years ago when one of our feline overlords ate just a mouthful of a toxic plant (lilies can kill!) and had to be treated intensively and then hospitalized for 3 days. The bill was $1,400.
My kitties are everything to me, so I paid it without a second thought, but I sure as heck didn't pay it with a smile on my face.
Having said that, do I have insurance now? No. I decided afterwards that the approach Spiderlashes suggested is best and I've simply been putting money aside regularly in case of future mishaps. There are too many caveats and cost limitations for many forms of pet insurance; I don't want to be paying for years, have something happen, and then hear, "oops, sorry, we don't cover that." My view is that it's best to keep the money in my own hands.