If you post on forums with your ICQ address visible or otherwise make your icq address available on any social networking site, you may be  a ripe target for a new scam being perpetrated online:

An ICQ spammer harvests your ICQ number
Spammer sends out an authorization request that looks suspicious (weird characters and other blocks) and it has a URL
You get suspicious because of the text and enter the URL into your browser
Their page is setup to hijack your browser

Be very careful of this newest attack method.  Keep your spyware and antimalware applications updated.