The recent, highly publicized series of hacking attacks worldwide has given rise to a new industry: consulting practices that field quick-response 'white hat' hacking teams that attack customers' sites and expose security vulnerabilities. Companies such as Price Waterhouse, Coopers & Lybrand, Ernst & Young and IBM are employing 'SWAT teams' to combat rogue activity. Price Waterhouse's Tiger Team has grown from 20 security experts to 200 worldwide. Prudential Insurance company of America used outside consultants to work over its IT infrastructure to shore up weaknesses. Security experts say that t he most glaring security weaknesses are usually the result of simple human error or not turning on security mechanisms in their operating systems.