The public library field is a bounty of data—the annual Public Library Survey (IMLS), Impact Survey (UW), Public Library Funding and Technology and Access Study (ALA/UMD), Edge Initiative, and other initiatives routinely collect data about what libraries provide for their communities and how patrons benefit from their resources and services. Mashed up with community data from the U.S. Census and other sources, the possibilities for playing with data are endless! Come see how researchers at the University of Washington Information School have been mashing up these data and looking for relationships between resources, patron outcomes, and community characteristics. They provide ideas about how you can do library data mashups of your own using community data together with data you are already collecting or can easily gather. The UW team unveils the beta version of GloPlug, their online data analysis tool built on the powerful new Shiny for R application. GloPlug lets librarians play with library data through a friendly interactive app and instantly produce easy- to-understand graphs and charts. See how your library stacks up against other libraries in communities like yours, how libraries divvy up their budgets, or just explore the data and get a new perspective on what libraries do.