I would like to start the IMSLP Orchestra, and to have them make the world-premiere recording of the Symphony in C major by Franz Asplmayr. It would be like the YouTube Orchestra, except the players would not necessarily have to meet, and some players could play multiple instruments (e.g., a bassoonist could play both bassoon parts). These would all be synchronized by a mechanical playing of my figured bass realization; each player would listen to the continuo through headphones, which would hopefully not bleed into the recording of their playing. Later on a skilled harpsichordist could give a less mechanical performance that would be integrated into the finished recording.
The mechanical continuo should be available on the same IMSLP page as the score and part PDFs pretty soon. The players could also post their individual recordings on that same page. In the MP3 format, 128kbps (mono) or 256kbps (stereo) will do just fine.
Carolus let me know about something similar that has been done with choirs: Eric Whitacre assembled a massive choir this way to perform his composition ''Sleep''. For this project, fewer players than a chamber orchestra would be required.