With no family to visit, Swan routinely worked through the vacation; she liked to have the company’s computer resources to herself. That evening, long after everyone else had gone home, Swan was still in her office on the third floor of the TLA building. A single strand of purple tinsel was taped to her office door in concession to the season. Swan was about to send an electronic message to one of her co-workers elsewhere in the building, and so wanted to see if they were still logged on to the machine or had gone home for the holidays. She typed in a short command: who And the terminal responded: sswanpts/0 Dec 24 17:48 jsmithpts/3 Dec 24 19:55 hostmastpts/5 Nov 24 04:07 uucppts/2 Nov 24 04:05 rootpts/4 Dec 24 00:01 Swan stared at the list of users for a moment. Who the hell was jsmith? Only members of the research team had access to the mainframe. (The other ‘users’ were automated programs.) Swan did some checking. No-one was dialled into the computer, so her intruder wasn’t coming in via a modem.