As technology become more complex, a group of brilliant entrepreneurs is using it to tackle some of the most fundamental human challenges of all time—clean food and water, adequate and affordable health care, accessible education, and the chance to live a better life. These 11 start-ups from 10 countries and five continents recently took a 100-day voyage around the world as part of the Unreasonable@Sea program. Co-sponsored by SAP, their incredible journey included stops at 13....