^This
Dropbox is amazing and I use to keep 2 macs, 1 windows PC and 2 servers in sync. It's never missed a beat and is fast, easy to use and well priced (free if you use less than 2gb of data)
On top of that, all your synced data is also available "in the cloud" and accessible from a phone, iPad or web browser anywhere
I use dropbox and have been for about half a year now; I use it to sync between my Mac, PC, and my phone along with my girlfriend's computer as well. Great program and 2 gigs is great for just about any file I would want to send.