On average, women live five years longer than men--which means they'll have to save for a longer retirement. Unfortunately, according to an article in today's New York Times, most women have saved less than men. There are a number of reasons for this, among them lower wages and years spent outside the workforce when raising children. Of course, the usual challenges of retirement are compounded for independent workers, who don't have access to employer-sponsored 401(k) accounts or pensions. Over at Lifehacker, readers sent in their own tips for saving as a freelancer. Check them out!