Workgroup software sharing was invented with shared hdd(netware). Since then workgroup is identified by security password for groups in the operating system, then to share a hdd by server/client or peer to peer relationship.

Today, in the definition of virtualization and oversight responsibility. Sharing the responsibility of any document involves shared responsibility for lack of errors and achieving perfection even.

So, email group listing, vacation auto-response with attached file is the simplest workgroup solution, but time consuming for file transfer attached by email. And there maybe conflicts in submission timing for error correction, which has to be resolved by reconciliation, by swapping corrections by people involved in the conflict privately(1993 technology).

Since then people started to use wiki format to make public corrections, once and for all to see. This is simple but can be troublesome to the extent that perfection can be corrected erroneously by people of less intelligence. So wiki format has to have quality control with inspector approval signature to lock in the final version.

Others are very complicated. I am sure you could copy the technology of Sharepoint by Microsoft, and all the other workgroup applications too. Watch out for patent applied for?

This, however, made wiki workgroup format perfectly suitable for Ulteo, Ajaxwindows and Google apps to extend desktop to SOA server workgroup apps. Google apps may already included Salesforce proprietary software to share info among workgroup members.

Even Tusmachines.org can add wiki for members to have fun and game to correct each other in Drupal with final approval unanimously by signatures.