As if users did not have enough worries about viruses hitting their PCs (whether at home or at work), the latest Trojan hit mobile handsets running Symbian-based OS.  The latest piece of malicious code has been dubbed "Skulls" by the anti-virus experts, and comes disguised as a theme manager for Nokia phones in the Symbian Installation Format, such as the 7610.   The virus kills off system applications and then replaces their icons with skull images.

But Skulls is not alone in Trojans creating havoc for cell phone users.  A program called Delf, was used in Russia to infect PCs so that spam could be sent to mobile users across Russia.  Similar viruses have been written to attempt to infect devices such as PDAs running on Windows CE.  Hackers will be increasingly focusing on creating viruses that can infect mobile handsets.