Medical technology offers enormous potential for scalable medicine--to improve the quality and access in health care while simultaneously reducing cost. However, current medical device innovation within companies often only offers incremental advances on existing products, or originates from engineers with limited knowledge of the clinical complexities. We describe how the Hacking Medicine Initiative, based at Massachusetts Institute of Technology has developed an innovative "healthcare hackathon" approach, bringing diverse teams together to rapidly validate clinical needs and develop solutions. Hackathons are based on three core principles; emphasis on a problem-based approach, cross-pollination of disciplines, and "pivoting" on or rapidly iterating on ideas. Hackathons also offer enormous potential for innovation in global health by focusing on local needs and resources as well as addressing feasibility and cultural contextualization. Although relatively new, the success of this approach is clear, as evidenced by the development of successful startup companies, pioneering product design, and the incorporation of creative people from outside traditional life science backgrounds who are working with clinicians and other scientists to create transformative innovation in health care.