SharePoint users can synchronize their documents with the SkyDrive Pro client (not to be confused with SkyDrive).
Unfortunately, the SkyDrive Pro client is not available on Mac (and Linux), and even if you are on Windows, in addition you must pay for Office 2013 Professional Plus before using it.
Microsoft shows no sign of clemence towards Mac users on this matter.
Using Parallels does not help: My Documents is then seen as a network location, which means that Skydrive Pro fails to save documents there.
But here is new hope!
CmisSync allows you to sync SharePoint to your desktop, no license fees, and Mac/Linux versions are planned.
CmisSync is currently Windows-only, but it is Open Source and looking for volunteers to port the code. CmisSync is built with Mono, which means it should be easy to port it to Mac/Linux/Android/iOS. So please developers plunge forward and don't hesitate to ask us questions :-)