A teenager commits suicide after being blackmailed by a Romanian guy over masturbating on webcam. Then there's this article, amounting to something similar.
It's very difficult for me to empathise with cases like these. One night you have nothing better to do and accept a Skype connection out of the blue, start chatting and before you know it your developing emotions are exploited to get you to send money away, show yourself in compromising stances on webcam (or on audio recordings). Nobody expects it but there are people so good at manipulating and reading people and getting others to open up (particularly friendly people who are willing to open up to strangers anyway) and then using that knowledge for their own purposes.
It's not difficult to get something compromising out of someone. It starts with a friend request out of the blue (I know I'm getting a couple every week over Skype, even though my profile is only partially public). The person on the other end has research you already, your email, your name, location, profile (everything they can get publicly on Facebook/Skype/Whatsapp/Linkedin or even older profiles you thought dead like MySpace or Yahoo). Even if your friends list isn't public, they can still compile a list of your friends (after all not everyone makes their friends list private).
There are few things harmless in the world and social networking is definitely not one of them. And it all boils down to personal responsibility. You have nothing to do but let unknown, unseen strangers get in touch? Your girlfriend was away so why not masturbate online together with a stranger? Sure, it's your right, but as long as there's another person involved, you need to evaluate the degree of trust that exists. Trust isn't something given but earned and so easily exploitable.
The only thing I take away from this is that actions have consequences, whatever you do (or don't do) has some outcome. Be sure it won't bite.