I am working on getting our Linux (and eventually Windows if possible) systems setup so that we can monitor administrative changes and have a history of them to refer to. Currently, I have a pretty good setup going with etckeeper, logwatch, and mercurial.
I would like to make this just a bit more robust by nagging any admin when they logoff with a message that asks them if they would like to create a changelog for what they just did on the server. A "no" answer would continue the logoff process and a yes answer would take them to whatever editor they use where they could enter whatever they wanted about what they just changed on the system. The changlog helper would then add some standard formatting to what they put there (add a date/time, username, indent, rewrap to 70 chars per line, etc.) and prepend that to a file somewhere on the system. I would then include that changelog in the monitoring setup I have already which would result in it being version controlled and sent to a centralized location.
I am envisioning something that would look and work very much the way the commit/comment feature works with mercurial/git/svn, except the comment gets formatted different and saved to a file locally. Bonus points for having some pre/post commit hooks or otherwise being able to customize it.