Wall Street Journal piece found via Freakonomics explains how not using your health insurance can save you some serious bucks:

I explained that just because he had health insurance didn’t mean he had to use it in every situation. After all, when people have a minor fender-bender, they often settle it privately rather than file an insurance claim. Because of the nature of this man’s policy, he could do the same thing for his medical procedure. However, had I been bound by a preferred-provider contract or by Medicare, I wouldn’t have been able to enlighten him….

Most people are unaware that if they don’t use insurance, they can negotiate upfront cash prices with hospitals and providers substantially below the “list” price. Doctors are happy to do this. We get paid promptly, without paying office staff to wade through the insurance-payment morass.

So we canceled the surgery and started the scheduling process all over again, this time classifying my patient as a “self-pay” (or uninsured) patient. I quoted him a reasonable upfront cash price, as did the anesthesiologist. We contacted a different hospital and they quoted him a reasonable upfront cash price for the outpatient surgical/nursing services. He underwent his operation the very next day, with a total bill of just a little over $3,000, including doctor and hospital fees. He ended up saving $17,000 by not using insurance.