The Disk Cleanup wizard and I have been on something of a journey. I used to think that it was for newbies who were wondering why the magic bucket of space that was their hard drive had somehow filled up, and they should just learn how to use a computer properly. Still, over time the Disk Cleanup wizard saved my hard drive bacon enough times for me to use it quite a lot - when you just want to clear out a load of temporary files NOW, goddammit, it was genuinly useful. Its no substitute for knowing where to look for some really big useless directories of course (c:\windows\system32\logfiles and c:\windows\servicepackfiles\ on a 2003 Server spring to mind), but hey.
And it can't be big. I mean, really. Its titchy. The executable is 208kb.
So why does Windows Server 2008 not have it installed by default? No idea, and the really odd thing is where its hidden - in the Desktop Experience Feature. You enable that and a few things happen. 40mb of space disappears, you get Windows Media Player (useful, I mean I am just about to go to the server room right now and plug some speakers into a Blade so I can watch a DVD or something). You get the opportunity of hacking the registry to display Aero. You get Sound Recorder, Windows Mail, the PHOTO GALLERY for pity's sake. What has this got to do with disk space issues? Well mainly all these apps are capable of filling your drive up with personal data.
Maybe the logic is if you have all these home apps on a server you probably NEED the disk cleanup wizard.
But the thing that really grates is that you need to reboot. No ifs or buts, the files are just not there until a reboot. Which if you have a server out of space which has to stay up is Not A Useful Engine.