In Windows 2000 you have mucho more control on the priorities of the different processes (look at the post by Paolo Messina). I tried once (in Windows 2000) to place the seti process at realtime priority, and I can tell you it did exactly that. I could do nothing more that use that application. No switching, no mouse (keyboard still works), no paging, the closest thing you'll ever see to a real time OS in Windows.:)
