I was kind of amazed to learn that apparently if you connect Windows NT4/98/2000/ME to a public IPv4 address it gets infected by what is a period correct worm in no time at all. I don't mean that someone uses an RCE to turn it into part of a botnet (that is expected), apparently there are enough infected hosts from 20+ years ago still out there that the sasser worm is still spreading.
I still remember how we installed Windows PCs at home if no media with the latest service pack was available. Install Windows, download service pack, copy it away, disconnect from internet, throw away everything and install Windows again...