SUBSPOT networks

anyone else seen any evidence of this? ive been googling around and it seems to be genuine, but apparently there is basically a backup wireless network in place incase we have a nuclear war or have our phone networks blasted out in a terrorist attack. Not sure how it all works, but there have been reports of people getting this: (ripped from another site)

anyone had this? not had it myself but having hacked my iphone to bits the icon doesnt even exist in the file system, so even this must be remote?
ODD