At our church we have two PC' side by side. One for EW and projection to the main screen and foldbacks, the second is running VMix video mixing for recording the service.
Since recently having a good high speed internet connected, the guy who did that have linked these PS' using Bit Torrent Sync.
That means we can keep certain files always in sync on both PC's. It works well for certain things.
Last week I was wondering if we could sync all data and media on both PC's which would give us a full backup of our main projection PC.
The guys who know the software said no problem, and I could even sync my PC at home ensuring the database on all 3 PC's was exactly the same. Very handy as I have been doing it manually. It would also give a great way to keep and up to date backup of all songs in our database (we recently had a hard drive failure of the main PC but I had only just done a backup of the Data files!)

What I am wondering is, if I start up all 3 PC's and add a new song to the database on say the Video PC, while the main PC was using the database for live projection, would that crash EW on the main PC or would EW be OK with it?

If this works, it would be a great way to load a new song to the church PC - from home seeing I can't add a new song to the database as we did in EW 2009. That is, I add a song to my home PC database, go to the church and start that one up and it will automatically sync the two PC's at the church with the one at home - and vice versa. But if the church PC was in live use using its local database file which was being remotely updated, would that cause a problem to EW?

If so I might have to do it a different way by making a copy of that database file and scheduling the sync, or syncing a copy from another folder and manually switching it when I go to the church.

I could now do it using Dropbox but would have to manually replace the database each time I made a change either way and I am not sure I want others playing with the database files.