I recently noticed that whenever I visited certain non adult related websites I got a barrage of adult popup windows. I then found out this was a virus, the virus is called JS.Fortnight.B@mm which is activated by the following means,
"The mass-mailer arrives in infected e-mails, that have the signature as a "s.htm" file, so when the infected e-mail is open, using IFRAME, the virus remotely executes its infector (another html) and infects the current user."

The above text was taken from this page,
http://www.bullguard.com/virus/135.aspx

Its damn hard to remove and I found the following thread at a techie forum,

http://forums.t2.net/postlist.html?s...75&showforum=3

Anybody else come across this menace and if they did how did they get rid of it.