I have been wanting to boot NT for a while. I wanted to get a couplw flasg deives I just had LYING around, and boot the LATEST service pack of NT4 and Win3.1 bual boot on it. How do I do this, and can I do it legally? What size flash drive will I need?Maybe a quad boot with a newer version of Win95, Win98, NT4 (latest service pack), and Win3.1?1. Versions of Windows before Windows XP cannot be booted from a USB Flash drive.

2.XP And Later can be made to boot into a "LIVE" environment but they require a very familiar and technically competent user to both PREPARE and use.

3. Booting Windows from a USB Flash drive is arguably a violation of the EULA. At best, you'd need to own a copy of the OS.Right. What BC_Programmer said is true

Here is what you can do and stay legal.
Acquire an older computer that has NT available.
Use it to try any standard NT program. You can use Ethernet to TRANSFER results to a modern computer.

Source:
A. Personal experience.
B. Current eBay listings

You can find a legal Windows NT install diskettes for under $50 and a old Thinkpad will go for about $150.
Okay, thank you for the advise. Will look at that. Topic solved.