http://www.theregister.co.uk/2005/09/05/smut_censoring_trojan/
"Virus writers have created a Trojan horse which tries to disrupt visits the pornographic websites by displaying messages from the Koran.
The low-risk Yusufali-A Trojan horse monitors the websites Windows users are visiting. If the malware sees one of a set of trigger words (such as 'teen', 'sex' or 'penis') in the url it minimises the window so the user cannot see its content and displays a message from the Koran instead."
