As new sculpts/models, sometimes with multiple versions, as well as maps, FBX files etc.. are created organizing everything can become very hectic and even harder to find things later for reuse.

With zbrush I'm sure everyone has different methods that work for them as well as the endless pipelines that can flow with zBrush but ultimately my question is how does everyone keep all these file organized from not only zbrush but the other software in their pipeline?

Is there a software out there to help with this nightmare (With thumbnail capability and Preferably Free if possible)?

I have looked at Git which is free but that appears to be more of a code repository.

Also should be Mac and PC compatible as I primarily work on Mac but use both.