You can use Doors to achieve the following:
Perform (cf. Jean-Michelle Jarre)
The goal of Doors is to allow electronic musicians to perform live.
Many such musicians may be content to press the start button of a sequencer and then play with faders & sliders which constitute the 'live' part of the act. The Doors system, however, will let an electronic musician spontaneously choose any content for playback, which will be seamlessly integrated with what is currently being played. The musician is still free to play with sliders, of course. (And "Input Devices", which is a future development.)
Jam
Rather than perform in concert, users may also informally 'jam' together and experiment with combinations of different musical parts. This may be especially interesting for users with no conventional musical skills, who will now able to create music and play alongside other musicians.
Note also that musical content is accessed via URLs. This means that if users have an Internet connection, they may browse and play Parts directly from any web site which hosts such content.
Control Digital Art Installations
Doors can be used as the controlling software behind interactive art installations. Any type of hardware device may be controlled, assuming the corresponding (software) Device has been developed. The Doors framework could be used to passively playback media/data, or may actively control devices based on data read from input devices.
Automate Buildings
The Doors framework controls distributed hardware devices with millisecond accuracy. Therefore it can also control heating, curtains, lights, coffee-machines etc. and provide all the advantages of networking, Corba, error-handling etc. that are required by musical applications. This could be used in automated houses, offices, cinemas etc.
Furthermore, Doors would be perfectly suited to controlling the shows in a planetarium (especially Pink Floyd laser shows). The portability features of Doors would ease taking the show to venues which have differing sets of hardware.