Microsoft SharePoint® is, of course, a collaboration and versioning product that these days has a lot more to it than just its web interface. Here are a few links that you might find especially useful to get you started:
- “Perltopus” (at github)
- http://sharepointconnoisseur.blogspot.com/2011/05/401-unauthorized-error-when-integrate.html (he didn’t fully solve the problem but he talks a lot about what he did)
Even though SharePoint has a touchy-feely “I’m a web site” interface, the real meat-and-potatoes guts of the thing is a software service that is most easily accessible using SOAP and DAV.
This has been talked-about around here before, too, so use Super Search: