Several new viruses, though not ranked high on the threat scale, are newsworthy because they have implemented new and interesting technologies. The Romeo and Juliet virus exploits a Microsoft Outlook security hole discovered by bug hunter Georgi Guninski. Also called "BleBla" by some antivirus firms, it can infect users who view or preview e-mail that Outlook runs as a Webpage, enabling malicious script.

Another Internet worm known as Hybris seems to be the most complex virus in the wild today. It uses up to 32 encrypted plug-ins to change its own constantly updated features, camouflages itself in e-mail written in four languages, and posts a status log to virus-related newsgroups so it can communicate with itself. Eugene Kaspersky, head of an anti-virus research firm, said Hybris is "perhaps the most complex and refined malicious code in the history of virus writing."

Hybris appears as an e-mail attachment from someone the victim corresponds with. If the attachment is opened, Hybris infects Winsock32.dll, on the host computer, and will store a copy of itself in the Windows system directory and begins searching for outgoing e-mail messages to infect.

For more on Hybris, read zdnn.com. Information about Romeo and Juliet is at msnbc.com.