A computing environment includes client computers in communication with a mainframe computer. The mainframe computer stores customer data under keys. A client computer is adapted to execute one or more application programs and a desktop bus. Each application program has a bus interface component for enabling the application program to communicate with the bus. Upon execution, each application program preferably registers with the bus. When an application program learns a key from a source other than the bus, the application program sends a message to the bus including the key. The bus stores the key and, depending upon whether another application is designated as either "hot" or "cold," either sends the key to the application or notifies the application that the key has changed. In response to receiving the key, the application accesses the mainframe to retrieve the associated customer data.