I developed a Piki tool to help runners choose the best marathon for them. A Piki is basically a new way for people to search for items based on their specific preferences. You can choose one important factor, such as the best marathon for low registration fees, comfortable weather, or high participation. Or you can adjust a variety of criteria, including temperature, prize money, elevation, time limit, and others. As you choose what requirements are most important to you, the Piki will automatically compile a list of U.S. marathons that best meet your needs. I'm hoping this can help people out since there are so many marathons out there. Please check it out and give me some feedback. I'd love to hear what you think.