Wired magazine gives a defining comparison between the great greek myth and one of today's most effective virus methodologies.
1184 B.C.: During the Trojan War, the Greeks depart in ships, leaving behind a large wooden horse as a victory offering. It is hauled inside the walls of Troy, and Greek soldiers descend from the horse's belly after dark to slay the guards and commence destruction of the city.
You, of course, could only lose your data, your hard drive, your thesis, your job, your money, your business, your identity or some awful combination of these.