Remember when we said that DRM and its ilk were such a very bad idea because - among so many other reasons - when it all goes wrong, it goes really badly wrong?
Looks like we're in the early stages of a masterclass in this. Microsoft's Windows Genuine Advantage - the DRM system that turns chunks of your operating system off if it thinks you're a criminal - now thinks that we're all criminals. More precisely, MIcrosoft's WGA servers are down (link via BoingBoing), with the company saying "try again, we should fix them by Tuesday"; the result is that whenever a XP or Vista installation tries to make contact to confirm its legality, it fails. And then turns stuff off.
So whatever you do, don't make your Windows installation try to call home. No new Microsoft software, no patches, no updates. I'm not sure exactly what happens with Vista - I stopped running my copy because I needed that machine for Linuxy things - but reports on the WGA forums suggest that if you reboot Vista at the moment, your Aero stops working.
Don't need to say anything more, do I...
[Update: all working again now, as of Sunday morning UK time. More on this next week, doubtless)