We have created an experimental prototype that enhances an ordinary personal media player by adding digital library capabilities. It does not enable access to a remote digital library from a user’s PDA; rather, it runs a complete, standard digital library server environment on the device. Being optimized for multimedia information, this platform has truly vast storage capacity. It raises the possibility of not just personal collections but entire institutional-scale digital libraries that are fully portable. Our implementation even allows the device to be configured as a web server to provide digital library content over a network, inverting the standard mobile client-server configuration and incidentally providing full-screen access. Anecdotal yet compelling evidence as to the usefulness of being able to access a self-sufficient digital library anytime, anywhere is given through an example built from the PDF files of the Joint ACM/IEEE digital library conference. Other examples include the Complete Works of Shakespeare and collections on Humanitarian Aid. This paper describes the facilities we built, focusing on interface issues that were encountered and solved.