As many readers know, the end of October in the US features the holiday of Halloween. The sight of youngsters and adults costumed as ghosts, witches and other-worldly creatures approaching houses and knocking on doors with the words “Trick or treat”. In response, the residents pitch sweets into the children’s bags or run the risk of egging of the home, soaping of the windows or worse. This year, information security professionals globally got a chance to vicariously share in the tricks and treats dished up by as yet unidentified members of the hacker underground in their efforts against mighty Microsoft. The primary incident involved unknown person(s) who were able to obtain access to Microsoft’s internal network and was described by the company spokesperson as an “act of industrial espionage”. This very high profile intrusion apparently began in mid-October and remains an open investigation. The publicly available information is significant and bears close study by those who must defend organizations against similar depredations.