In our health-conscious society, viruses of any type are an enemy. Computer viruses are especially pernicious. They can and do strike any unprotected computer system, with results that range from merely annoying to the disastrous, time-consuming and expensive loss of software and data. And with corporations increasingly using computers for enterprise-wide, business-critical computing, the costs of virus-induced down-time are growing along with the threat from viruses themselves. Concern is justified - but unbridled paranoia is not. Just as pr ....