While a lot of technical data is available on the Web, conveying information about detailed procedures for the assembly and repair of complex machinery has so far been limited mostly to 2D drawings and textual content. In this paper we describe the technology behind our 3D Wiki, a system meant to address this problem. By blending the functionality of virtual worlds (3D visualization and navigation) with the benefits of social software (editability, traceability, and hyperlinking), the 3D Wiki can help users tasked with the remote maintenance and repair of technical equipment. Our environment provides a kind of “living technical manual”, seamlessly blending spatial and textual content.

This article describes an infrastructure that supports the creation of interoperable systems while requiring only limited prior agreements about the specific forms of communication between these systems. Conceptually, our approach uses a set of “meta-interfaces”—agreements on how to exchange new behaviors necessary to achieve compatibility at runtime , rather than requiring that communication specifics be built in at development time —to allow devices on the network to interact with one another. While this approach to interoperability can remove many of the system-imposed constraints that prevent fluid, ad hoc use of devices now, it imposes its own limitations on the user experience of systems that use it. Most importantly, since devices may be expected to work with peers about which they have no detailed semantic knowledge, it is impossible to achieve the sort of tight semantic integration that can be obtained using other approaches today, despite the fact that these other approaches limit interoperability. Instead, under our model, users must be tasked with performing the sense-making and semantic arbitration necessary to determine how any set of devices will be used together. This article describes the motivation and details of our infrastructure, its implications on the user experience, and our experience in creating, deploying, and using applications built with it over a period of several years.

Peer-to-peer systems appear promising in terms of their ability to support ad hoc, spontaneous collaboration. However, current peer-to-peer systems suffer from several deficiencies that diminish their ability to support this domain, such as inflexibility in terms of discovery protocols, network usage, and data transports. We have developed the Speakeasy framework, which addresses these issues, and supports these types of applications. We show how Speakeasy addresses the shortcomings of current peer-to-peer systems, and describe a demonstration application, called Casca, that supports ad hoc peer-to-peer collaboration by taking advantages of the mechanisms provided by Speakeasy.

In this paper, we describe FLANNEL, an architecture for adding computational capabilities to email. FLANNEL allows email to be modified by an application while in transit between sender and receiver. This modification is done without modification to the endpoints---mail clients---at either end. This paper also describes interaction techniques that we have developed to allow senders of email to quickly and easily select computations to be performed by FLANNEL. Through, our experience, we explain the properties that applications must have in order to be successful in the context of FLANNEL.

Users in ubiquitous computing environments need to be able to make serendipitous use of resources that they did not anticipate and of which they have no prior knowledge. The Speakeasy recombinant computing framework is designed to support such ad hoc use of resources on a network. In addition to other facilities, the framework provides an infrastructure through which device and service user interfaces can be made available to users on multiple platforms. The framework enables UIs to be provided for connections involving multiple entities, allows these UIs to be delivered asynchronously, and allows them to be injected by any party participating in a connection.