> I imagine they are in a tough spot: how will they ever make any money off this product if it's fully open source? The whole point is that it needs no central server.

Every day we, as well as general consumers, pay money for someone to run something for us because we don't care to run it. I can run a mail server. But please, please please, take my money to do it. I like to sleep, I like my mail to work, and I like to work on more exciting projects.

Bittorrent should open the code with a license that permits them to run a service they can charge for, but anyone else can use for free.

Doesnt the GPL allow that

Yes, presuming the above was not meant to include "... that other people cannot charge for".

You're correct. Thanks for adding that.

I have not done more than look at it so far but I heard good things about it when it was still called Syncthing. As for making money off OS code there are a number of companies doing it (Free code + paid services). BTSync could offer help to enterprises setting it up internally, they could offer a cloud to sync your data to (encrypted), they could offer pro-features (like some stuff Dropbox offers). The whole point is that it needs no central server but the sheer existence of an API key means there IS a central server that this all relies on...