remote file sync

I have a PC and Mac in different cities, and I would like to set up two-way syncing between a folder on each of them. Essentially dropbox without the middleman, and without capacity limits.

I've looked around a bit and it seems GoodSync will do what I want (supports mac and PC, remote bi-directional syncing) but I'm not too thrilled about the licensing cost. Does anyone know of a way to set this up using freeware?

Bittorrent Sync is awesome, and it's free.

http://www.getsync.com

Wow, awesome indeed! This is exactly what I was looking for. I even get mobile sync, too. Thank you.