Behind the scenes at WikiPedia, they have an amazing online collaboration / revision tracking system set up. Unlike many businesses today, the admins at WikiPedia do not send around copies of Word Documents, hoping that everyone is working with the latest version. No, instead, they have a discussion board and version tracking enabled for each and every article. These tools make managing the site VERY easy, when comparing the alternatives.
So, what can businesses today learn from WikiPedia? Efficiency. If you frequently find yourself sending around multiple versions of the same file, struggling with "Track Changes" in MS Word, and are tired of hearing, "Can you email that to me again? I lost it" - then you should consider a program like MediaWiki. It's an open-source (free) program. You can use it internally - password protected, login required, etc - or, make it a public resource for your clients. It's a great way to put resources on your web site - manuals, tutorials, etc...
[edit] Great article on using a Wiki in the Workplace:
Welcome to the Wiki Party [/edit]