In house, the only software I could think of off the top of my head that is built for interdepartmental company use that includes blogging, forums, wikis, chat, file sharing and other collaborations is Microsoft SharePoint, but that solution may be expensive. Microsoft also has a hosted equivalent service that may be better in terms of price and scalability. However, if you are working with government contracts, the software may already be vetted for secure use, and may be covered by existing licensing or purchasing agreements.

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The best way to learn anything, is to question everything.