1. A method for intercepting and servicing selected requests of a software application running on a computer that uses an operating system and a local database to maintain configuration data to be accessed by programs running on the computer, without installation of the software application on the computer, which configuration data would normally include further configuration data of the software application, the method comprising: providing one or more data repositories containing the further configuration data, not stored in the local database, comprising one or more registry keys; virtually combining the one or more data repositories with the local database to create a virtual combined database corresponding to a database structure that the software application would encounter if the application were actually installed; intercepting selected requests of the software application; and servicing the selected requests of the software application using the further configuration data provided in the one or more data repositories, so as to retrieve the further configuration data while running the software application.