Is it possible to share one file/folder amongst multiple sites from within Alfresco Share? For example, a Marketing site that has a folder with 'emergency procedures' documents, and an Emergency site that has all the documents for all emergencies for all departments? Seems like a waste to duplicate the document in both sites.
Share doesn't yet have the ability to create links, however the Explorer client does. You can use the clipboard to create links to your originals. The latest (HEAD / will be 3.4.c) version of Share handles cross-Site linked documents and folders correctly.