We motivate the use of desktop assistants in the context of web surfing and show how such a tool may be used to support activities in both cooperative and personal surfing. By cooperative surfing we mean surfing by a community of users who choose to cooperatively and asynchronously build up knowledge structures relevant to their group. Specifically, we describe the design of an assistant called Vistabar, which lives on the Windows desktop and operates on the currently active web browser. Vistabar instances working for individual users support the authoring of annotations and shared bookmark hierarchies, and work with profiles of community interests to make findings highly available. Thus, they support a form of community memory. Vistabar also serves as a form of personal memory by indexing pages the user sees to assist in recall. We present rationale for the assistant's design, describe roles it could play to support surfing (including those mentioned above), and suggest efficient impl...

Abstract. We have developed a system, called Silhouettell, that provides awareness support for real-world encounters. Silhouettell uses a large graphics screen. People's locations (who and where) are projected as shadows on the screen. The feedback from the shadows allows people to naturally know each other. Silhouettell also selects and presents topics common to two to or more people to make conversations easier to start. The current implementation uses World Wide Web (WWW) pages as the material describing the common topics. Experiments with three users are reported to show how Silhouettell works in practice. We also examined where the system would be best used by polling people from various nations. 1