The brain tumor came back. An ugly mass growing in plain view threatened Karen Niles' remaining eye. She needed more surgery. This time, however, her medical plan wouldn't pay. It sounds like one of those insurance "horror stories" that President Barack Obama hammered home during the fierce debate to pass his healthcare overhaul. Except Niles' plan ended up as the beneficiary of a rare exemption to the new law --- a waiver highlighted in the plan's promotional materials. The plan didn't come from an insurer, but from a religious "healthcare sharing ministry." Consumer advocates call them a gamble. These plans successfully lobbied Democratic lawmakers to free their members from the requirement that everyone in the country have health insurance.