I do use Syncthing as a Dropbox replacement because that was my original use case.

My original user case was to sync files between my computers at work and home and it worked perfectly for that. Extremely reliable as others have mentioned.

But today when I started the program on my laptop while Syncthing was running on my computer it suggested the shared folder on my computer to sync. I knew it did LAN sync but I didn't know about the discovery. It was awesome.

Thanks to everyone who created this wonderful software.