Portable computing devices automatically interface with other computing devices to interact in a collaborative effort toward providing a single, seamless computing experience for a user. As a user walks into a room with a cellular telephone certain functionality and data can be automatically unloaded to a desktop computer or other device based on a user or device identification or state. For example, a conversation on a cellular telephone can be automatically migrated to a desktop telephone as a user sits down. As a user is about to leave a room for a meeting, the desktop computer can update the telephone with latest versions of certain files. Thus, devices can automatically aggregate and/or decouple to provide a user with a single computing experience. These portable devices can broadcast an extensible set of services to other devices as well as to a host computer or server.