This is a fantastic project. I've played around recently with late-90s/early-00s PCs, and have used Plop 5 on CD to boot off the USB disks. If you use older hardware, keep a copy on CD - booting off USB is much faster than CD!

I am curious (really, not sarcastic) why you want to play around with PC's from that period.

I am facinated by vintage computers. Computers from before that era feel exotic and unique but not so much for PC's.

To me a more modern OC does everything of an old one but more slowly. Not much to discover. Am I wrong or missing something?

They're what I have access to (for free; I don't buy this stuff), and what I grew up with. I used Pentium IIs and Pentium 4s (and some PowerPC Macs) in my early days. Exploring the limitations of older software or trying to cram newer software on to these machines is fun.

I don't get nostalgic feelings from a C64 or Apple 2 or TRS-80 because I've never even seen one IRL before. For my leisure time I want to play with something I'm mostly familiar with, because that's relaxing. I would jump at the chance to score a free Amiga or other hardware older than I've ever used, but just haven't had any presented to me.

I still go and repair computers for people who have older systems, and there are plenty of these still around. Many people either don't want changes (usually older people), or they can't afford newer systems.

The Plop boot managers are very useful tools for both physical hardware and for VMs.

I used to use these tools a lot, for booting Linux from USB on machines that only supported floppy/CD boot, and occasionally for booting from CD on machines that only supported floppy boot.

Note: this does not just mean physical machines.

I have used several hypervisors in which VMs could not boot from USB devices, well within the last decade. You can boot the Plop boot manager from a virtual floppy or virtual CD, and then start the VM from a real physical USB key that is attached to a physical USB port which is assigned to the VM.

This is a useful function: for instance, one can install DOS onto a USB key from inside a VM, then stop the VM to readily put files onto, or take them off, the key. That works with a physical partition too but most modern OSes do not play nicely with DOS. Linux does, but Windows doesn't.

You can install Linux onto a USB key and boot it both from within the VM and on bare metal. Note, not copy an ISO image, I mean a fully-installed Linux system. The VM continues to be useful because if you update the Linux-on-a-key, it will tend to add any OSes on the hard disk in the PC you are using, which you probably do not want. Update in a VM and this doesn't happen.

These are great for booting from USB drives on systems that are too old to support that natively.

So where do you boot it from in the first place ? Floppy ?

Either that or CD. I used this to install an OS from USB on a PC from 1998 that has a USB port but can't boot from it.

I used this to allow me to boot to a physical USB key passed through to a VMWare ESXI6 VM. I haven't used VMWare for a long while now but it wasn't possible to do this directly at the time, but a small plop iso could hand booting off to the USB Key. It is a fascinating utility.