I believe you're thinking of Microsoft Office. The retail versions of Office allow you to simultaneously have it installed on your desktop system and also your laptop, assuming your laptop is primarily for your use when you're away from your desktop. Not sure about the OEM version of Office. But it's never been that way for Windows.
I've seen people who look at the COA sticker for Win2000 or WinXP Professional Edition, and they're all "oh, for 1-2 CPUs" and they think "CPU" means a whole computer, not a little square thing that goes in a socket on the motherboard. What's that they say about the word "assume...?" 😉