Today, most computer users work with traditional hierarchical file systems for organizing large amounts of personal files. Recently, tagging has grown popular as an alternative means of organizing information resources. We argue that tagging is a powerful paradigm for efficient information access which overcomes many deficiencies of hierarchical file systems, especially in the context of the organization of large quantities of personal files. In this paper we present TagFS, a filesystem with tagging support which aims at a seamless integration of the tagging paradigm with local applications. While retaining the notions of directories and files and providing all standard filesystem operations, the semantics of these primitives are changed to modifications of the tag annotations.