JFS is a simple, TCP/IP based network filesystem protocol. It allows applets running in a Web Browser to load and save files on a remote server, as well as send email and print documents through the JFS server. Because Java applets cannot access the filesystem of the machine they are running on, this provides a useful way for applets to store state information.
The JFS clients, server and source code are free for non-commercial use, such as student projects and personal experimentation.