The document discusses designing a discovery-based travel search engine that helps users find new and exciting trip ideas rather than just providing the same popular options. It outlines some of the challenges in rapidly prototyping such a system, including developing the necessary search technology, providing real-time results, attracting users, and usability on different screen sizes. Feedback from initial prototypes revealed more work was needed, but the described process of iterative design, validation, and improvements led to the launch of a new discovery-focused travel search site in January 2011.