Deploy groupware tools, including good instant messaging (eg. Lotus Sametime: send msg to one or more hosts, have the client beep/flash to prompt users that someone is trying to contact them, etc.) that make it easy to share knowledge (technical notes to point users to), purchase equipment (if a user needs equipment, they only need to create a purchase request in the MIS database and are kept abreast of purchase/delivery details), solve help-desks issues (barring emergencies, problems should be handled by filling a basic help-desk ticket, so as to promote pro-activity instead of re-activity.
As of October 2K, it looks like no open-source solution matches what can be achieved with Lotus Domino/Notes.
Like all dep'ts, MIS needs to spend as little time as possible doing context-switch and putting out fires, and more time handling issues as part of a schedule. This leaves more time to think about future needs and problems). Consider advanced infrastructure management tools like Peregrine, PeopleSoft, etc.
Also remember that good indexing is a must!