Do Win XP programs run yet?

They do on WINE on ubuntu anyway

Yes, that's right. I was wondering if they worked on ReactOS yet.

...for good reason? Technologies from XP are by now insecure and obsolete. Why would Microsoft sell XP still? Does Ford still sell 1998 F150's at their dealerships?

It's a fairly straightforward cost-benefit analysis. Some of us rely on software that would otherwise be too difficult or expensive to replace, software that only runs on Windows XP for a variety of reasons. In my case it's a device driver that interacts with a very expensive flow cytometer. We've taken other precautions in order to protect the computer, and we're reasonably confident we can operate it safely. The same goes for many, many other Windows XP or Windows XP Embedded installations, where it's basically treated like firmware and carefully walled off from the outside.

Does "VM it" work? I mean, there is PCI and USB-passthrough in qemu, so this might be an option, especially since VMs are easy to sandbox (easier than physical machines where someone might simply plug a cable in so he can watch YouTube, for example).

Mitigations only make sense in a cost-benefit analysis when there's a corresponding threat. Why would someone bother with watching YouTube on a junky old PC in a corner of the lab? It doesn't even have an audio card, let alone a modern web browser. Besides, it's on an isolated VLAN and monitored (and backed up) like a server, so anyone messing with its network connection will cause the equivalent "server down" alert in our NOC, not that it will do them much good: This particular lab is in a pretty remote location where network bandwidth is at a premium, so we block YouTube campus-wide.

Frankly, I'm only really worried about malware somehow sneaking aboard the thing, which is why it's on-network in the first place. I don't want people plugging flash drives into it. And fortunately, there are still antivirus products that support Windows XP, which keeps the riff-raff out.