New post for Lifehacker: $1.1 billion in health insurance rebates were paid out this week to an estimated 12.8 million Americans. It’s part of the Affordable Care Act which requires insurers to pay rebates if they spend less than 80% of the premiums they collected on care (85% for group plans). Some came in the form of a check in the mail. If you got one, how about reinvesting that “dividend” back into your health? Here’s 10 cool ideas for doing it.