Regular Lifehacker readers will be familiar with Mozo, the finance comparison service which we talked about when it launched back in October. Using Mozo's personalised search tools, you can compare and shortlist products and check out reviews from thousands of real customers. If you've been giving your credit card a battering in the lead up to Christmas, you'll especially like Mozo's free Health Check service which shows you how to detox your debt by switching to a better value credit card for your personal financial situation. To celebrate the service, and because they're nice guys who know Christmas does terrible things to a person's wallet, Mozo is offering one Lifehacker reader the chance to get $500 paid off their credit card. To enter the contest, just log onto Mozo and take the credit card Heath Check. Then post the amount you would save by switching banks or cards as a comment back here on this post, along with a reason why you should be the winner in 25 words or less. Each entry will be individually judged and the most creative response will get the prize. There's $500 on offer; what exactly are you waiting for? The competition closes December 16, so get cracking! Check out the full terms and conditions here.