[anon-e-moose]

This is not a "bug" or a virus.

XP simply remembers the last ad-hoc network you connected to, to be used when there are no actual APs around. As a blindingly obvious differentiation, ad-hoc networks have a different icon and say "computer-to-computer network".

Back when Windows XP was introduced, ad-hoc was extremely useful as lots of places didn't have wireless internet access. My friends and I often used it to swap files or play network games.

If anything I would call this an unintended phenomenon of people just clicking something and hoping it worked. The network does not spread because of Windows, it spreads because people select an ad-hoc network without knowing what is.

Why we as a society think its totally great to be completely ignorant and reckless with our computers, I'll never understand.

[dedward]

It's an emergent behaviour of a complex system involving people and machines. What's fascinating is how this non-functional string/ad-hoc netowork beacon, whatever oyu want ot call it, with this specific name, has spread globally to every corner of the world as far as we can tell. Hit any airport or hotel lobby in the world where there are laptops around, and odds are you won't have to wait long before you see "Free Public WiFi" pop up. That, in and of itself, is fascinating. It's been going on for a decade.