OneSync as the name indicates is a freeware tool to sync folders, drives and also your Dropbox account. The best feature of OneSync unlike other sync tools is that it can sync network drives and also your DropBox account. Generally to sync your DropBox account online, you need to add files and folders to the DropBox folder in Windows, but with this tool, you can easily sync any folder just from the context menu of Windows.
The interface is very simple and plain, you can add any number of folder syncs by specifying the source and target directory. There is also option to add a Sync job from the Windows context menu.
You can see the video of OneSync in action.
OneSync is compatible with Windows XP, Windows Vista and Windows 7 (Support both x86 and x64).