Could you define "practical OS"? What specifically do you want this OS to be able to do? (Note that we've reached a point where no user necesarily needs to re

Could you define "practical OS"? What specifically do you want this OS to be able to do? (Note that we've reached a point where no user necesarily needs to restrict themselves to a single OS. They could use different OS's on the same computer for different purposes. This was not always so easy to do. It will continue to get easier.)