Managing storage in the face of relentless growth in the number and variety of files on storage systems creates demand for rich file system metadata as is made evident by the recent emergence of rich metadata support in many applications as well as file systems. Yet, little support exists for sharing metadata across file systems even though it is not uncommon for users to manage multiple file systems and to frequently share copies of files across devices and with other users. Encouraged by the surge in popularity for collaborative bookmarking sites that share the burden of creating metadata for online content [21] we present Graffiti, a distributed organization layer for collaboratively sharing rich metadata across heterogeneous file systems. The primary purpose of Graffiti is to provide a research and rapid prototyping platform for managing metadata across file systems and users.