ICQ application is one of the most spreaded Instant Messenger programs at all. And like every such utility program it has its own evidency of all communicating persons. This gigant centralized database contains many private datas that can be abusable. Becoz of a high spread of this system it is logic to focus on ways it would be able to abuse these datas for some malware code spreading. Just imagine it - worm that retrieves private datas of all accessible persons, composes e-mail messages and spreads itself to all addresses. Hard to say why there still had not happened such data compromity and following epidemy.