Don't get on the wrong side of the cyber vigilantes
If you are planning to be nasty to a cat or criticise earthquake victims for keeping your favourite shows off TV, watch out for the internet lynch mobs.
One of the more bizarre side-effects of the explosion in YouTube use and social networking has been the rise of online vigilantes exacting Old Testament-style vengeance on those they consider to be wrongdoers.
And their weapons are naming and shaming, disruptive pranks and the kind of abuse usually reserved for war criminals.
In recent extreme cases, victims of the virtual pitch-fork wielding cyber-mobs have had their bank accounts hacked into, seen their "crimes" reported to their employers and endured pranks such as dealing with endless hoax pizza deliveries.
One woman in the US had to seek police protection earlier this month after a video uploaded onto YouTube, which featured her racially abusing a postman, made her the target of hundreds of thousands of web vigilantes.
In China, a young woman who (very unwisely) criticised the blanket coverage given to the victims of a calamitous earthquake because it was interrupting her favourite TV shows was effectively hunted down and targeted with death threats and actual attacks on her home.
The most reported case to date has been that of notorious "Cat In Wheelie Bin Woman" Mary Bale.
The Coventry woman was caught earlier this year on CCTV footage pushing a cat into a wheelie bin.
It took just 24 hours for users of the controversial online message board 4Chan (a prime vigilante site dubbed the "online hate machine" by critics) to identify the woman on the grainy CCTV images uploaded onto YouTube.
As the influential online magazine boingboing.net reported: "Almost immediately after the video started making the internet rounds, the 4chan legion set out to find this woman and destroy her life.
"Within a few hours she was identified as Mary Bale, of Coventry (England)".
But there's more: they also found out where she worked. They posted the phone number and name of her boss. They found out where she lived, and posted a Google map of that address. They found her Facebook profile."
Bale, her friends, colleagues and family were deluged with thousands of hate-mails, she received death threats and abusive phone calls from all over the world.
Bale had become one of the growing number of victims of the web vigilante phenomenon.
Observers have talked about the internet's "collective hive mind" that reacts to examples of outrageous, anti-social or unseemly behaviour and sets about exacting immediate and wildly overblown retribution.
With virtually everybody in the developed world now having an online presence, it is relatively easy to track down and target individuals.
Large corporations have also been targeted with companies such as British Petroleum, in the wake of the Gulf Oil spill, being targeted by hackers and abusive mailers to the extent that IT systems were effectively shut down and frontline staff needed counselling.
Other recent examples include:
Dubbed the "Racist Rageaholic", this Massachusetts woman was filmed by a postal worker as she threatened, slapped and abused him in mid-October.
Within hours of the footage being uploaded, web-users had identified the anonymous woman as Erica Winchester and set about making her life a living hell.
Her Facebook account was hacked into, details of past-run ins with the police and neighbours were released and local pizza parlours suspended deliveries to her home after taking hundreds of hoax orders.
Police in her hometown of Hingham said such was the volume of abusive messages and phone-calls, they had no option but to give her round-the-clock protection.
However, they also decided to charge Winchester with assault and battery and committing a hate crime.
Teenage Smart Phone Thief Gets Hung Up
Sixteen-year-old New Yorker, Sasha Gomez, made a bad decision when she opted to steal a Sidekick II smartphone she found in the back of a cab.
Her victim had to buy a new phone and when she logged into her account, she found the amateur thief had unwisely uploaded pictures of herself along with her AOL screen name.
A friend of the victim tracked down the thief and sent her an IM asking her to return the phone.
When the friend was told in the most impolite terms possible to get lost, he created a webpage detailing who Gomez was and what she had done.
The page was linked to popular websites such as Digg and Gizmodo and from there to hundreds of other sites.
Hundreds of thousands of people read the story, remembered the last time they fell victim to a petty thief and briefly made the 16-year-old phone thief New York's Public Enemy Number One.
The real trouble started when somebody found out her address in Queens, New York, and people started driving past her home shouting abuse.
The young girl's brother eventually appealed for people to leave his sister alone, which provoked a new and more outrageous level of abuse. Gomez was eventually arrested for stealing the phone.
Zhang Ya Vs The Earthquake
By any measure, reacting to a horrific natural disaster that kills 68,000 of your fellow countrymen by publicly labelling the victims ugly drama queens is not a smart move.
A young Chinese woman called Zhang Ya not only did this, she uploaded a video of herself expressing joy at the deaths of some of the victims while saying she wished they had died sooner.
She also claimed some of the survivors were too ugly to be on TV and lamented that the news coverage was preventing her favourite shows from airing.
Ms Ya anonymously posted her response in the immediate aftermath of the Siuchan earthquake in 2008 and immediately earned the violent hatred of everybody in China.
She was tracked down within hours and after being targeted with epic levels of abuse and graphic threats, was arrested and held in custody for three days after personal information was posted online (and in such detail that people even knew her blood type).
The Chinese police also investigated a number of death threats that had been made.