The annoyance of using the internet
First was the win32.Conficker A and now the Koobface. koobface uses the social network to spread itself, facebook (primary target)
Those who wanna know more about this and ways to not GET TRICKED into downloading the worm. Lazy to read….aww..just hope you don get pawned. ^^
http://www.avertlabs.com/research/blog/index.php/2008/12/03/koobface-remains-active-on-facebook/