"The $100 Startup" by Chris Guillebeau. The book argues that it is possible to start a profitable business with very little capital, focusing on the stories of entrepreneurs who built successful ventures from their passions and skills. The book explores various aspects of micro-entrepreneurship, including crafting a compelling offer, building relationships, and navigating the challenges of running a small business. The author emphasizes the importance of understanding your customer's needs, providing value, and embracing the freedom that comes with self-employment.