DropSync is a tool for keeping folders on different computers or different hard drives in sync. It uses rsync to transfer only the parts of files that have changed, so it's fast, especially over a network.

Any task that involves repeatedly copying the same files or folders can be made easier and faster by using DropSync

Features:

• Browse: See folders side by side to easily keep track of things
• Works between computers: Connect with remote computers to work with websites or create remote backups
• Customise rsync options: Power users who know rsync can set options to their hearts content
• Detailed previews: View detailed previews of every sync
• Automate with Applescript: Customise syncing workflows with Applescript ... learn more
• Log everything: Keep a log of everything that gets synced

Requirements:
OS X 10.9+
64-bit Intel