Well, third voice used to make something where you could overlay sticky notes on any website.
If you created a website of nothing but a chart of your machine room, users could stick their names on any machines that were in use.
But they went out of business.
stickis promised the same functionality, but I think they are also gone...
so what about devote an otherwise idle computer to this use?
make the desktop wallpaper be a chart of the machine room, and just have users drag around icons with their names on them. They place the icons on the machines they're using and everyone can just use vnc to keep tabs on that computer when they want to make a change or check it out!