Not long after seeing this discussed on MetaFilter I was on WebCamNow.com on the adult section. (I admit to being fascinated by net sexuality.)
One of the cams was showing what could be taken to be a person being cut with a scalpel - complete with blood. I, personally, did not think it was real, but several people did and at least one said that the police should be contacted.
After the "ripper" incident, I was feeling a bit on the cautious side and tried to find a way that I could use to do something if I felt that things were getting out of hand.
While webcamnow provides email for support and the like, there is no clear way to contact them that is immediate and gets to someone responsible.
Furthermore, there is no obvious way to get an IP number for any given chatter or broadcaster. (I did find a way to get an IP number for a chatter, but not all broadcasters chat or even chat with the same nick.)
On IRC, and on ripper's webcam, finding the IP is pretty straightforward, but from there, actually reaching the person may be far more difficult. In this case, someone had the sense to do a whois but the phone numbers are fake (555 exchange).
Even given that you can get an IP its not clear to me that that will lead to a route to find the physical address needed to do anything in person.
For example, I have DSl through verizon - would you be able to get information to/from verizon quickly enough to respond to an event like this? (My experience with such has not been positive - on a local Search And Rescue mission a couple of years back we had a lost party with a cell phone and the cellular companies were almost no help for several things, and since it was a holiday finding out that they were no help took forever.)
Supposing you can get a real address (or phone number), the question of contacting the authorities is another tricky one. Ideally I'd try to find a friend locally to check on a person in a situation like this, but someone who spends lots of time on irc and the like may not have many local friends. Second, I'd try to find a local drug rehab or support group. And only last would I contact law enforcement. But which of these is likely to be most accessible over the net? Law Enforcement. And in this case I'd hesitate a bit before calling the police - the sheriff responsible for the phoenix area is quite proud of his hard line, aggressive, even nasty approach to drug users. Would being tossed into the criminal "justice" system have been good for ripper? He might still be alive, but on his way to 10 years in prison. Or 10 years in mental institution confinement.
Even granting that a viewer/listener/reader has access to a means to help someone, even granting that this is the right thing to do, its still necessary for the observer to determine that it needs doing. I started out watching someone doing something that looked like cutting another person's skin. It looked fake to me, but even granting that it was not fake it could easily be in the range of acceptable behavior to the people involved. At what point can an observer determine that the actions being observed are real and dangerous? IRC in particular is an environment that invites, even requires, fantasy. Webcams, while providing a visual look at things don't necessarily provide a real look.
Both environments also provide a social context. Read the logs of the last conversations involving ripper and see where (even if) you really decide some action needs to be taken.
This incident, while it stirs feelings of regret for the loss of this life, also raises questions that will perplex me for a while - those posted here among them, but others as well.