Blah ....license this!
I think eery OS I have ever owned has been installed on no less than 15 machines at a time.
I still run update once in a while with no problems.
The main thing is to not register it, do not send error reports, and don't ask MS for any help with it.
Never had a problem yet....I have done this with 98, 98se, ME, XP, and XP Pro.