There are a number of volunteering opportunities that can help you transition into a non-clinical career. For instance, you may wish to volunteer internationally through an organization like the Peace Corps. Before you know it, you may find yourself working as a medical officer, making administrative decisions in the world of medical management and networking with executives who have built careers in the non-profit sector. You may also find it easier to transition into public health jobs with the CDC or WHO if you have strong international health experience and exposure.
You can also volunteer your time by serving on councils and committees that may allow you gain the skills and leadership experience to break into a non-clinical career. Right now, a prime example is around the world of health information technology. Your hospital or group practice may have an informatics committee evaluating health IT resources, clinical workflow challenges, etc. By actively participating in your hospital IT committee, you may have the opportunity to establish industry contacts and understand some of the key issues that affect hospitals as they make decisions around electronic health records and computerized physician order entry systems.
So, do you have some time to volunteer? There may be some great opportunities to work in a free clinic and to get involved in your local community. While you're providing medical care to the underserved, you may get inspired to become a social entrepreneur.
Here's a link to a New England Journal of Medicine career article on physician volunteering. At the end of the article, they list a series of physician resources for those who want to spend some time volunteering.