An increasing number of Internet users now use Web feeds (or RSS feeds) to get their news, hear music and audio programs, and keep in touch. The result for website owners, however, is known as the "RSS bandwidth problem": because each feed reader polls every subscribed feed repeatedly for updates, the bandwidth demands of hosting a popular feed can be extreme. Our FeedTree system replaces this polling architecture with efficient and scalable application-level multicast based on the Pastry peer-to-peer overlay network. Instead of independently polling feed resources, FeedTree users cooperate to distribute feed updates; they substantially reduce the bandwidth burden placed on feed publishers, while updates arrive faster than with polling. In this thesis we explore the existing problems with Web feeds and describe the design and implementation of the FeedTree solution. We also share our experiences deploying FeedTree as a public Internet service.