Tracy Quek describes China's "human flesh search engine" at the Games.

In Beijing

YOU can run but you can't hide.

Well, not for long anyway. Not when there are millions of aggressive, enthusiastic, incredibly Internet-savvy Chinese netizens hunting you down.

China now boasts the largest online community in the world, surpassing the United States with more than 250 million online users registered. They are active in forums, chat rooms and are avid bloggers. They wield powerful influence, and as a single, massive entity can apply tremendous pressure.

It's become a phenomenon known as the human flesh search engine. This kicks into operation when a multitude of netizens decide someone has committed a heinous act, track him online and then hunt him down in real life.

Criticism by Chinese netizens, for example, prompted one of Chengdu city's richest property developers to apologise for his small donation to the earthquake relief fund and increase it by more than tenfold.

A woman who uploaded a video of herself grounding her heel into a cat's head, for example, received abusive phonecalls and emails. She was so vilified online that she was forced to quit her job and issue a public apology.

But, as the Beijing Olympics is showing, the human flesh search engine can also be activated for a good cause.

During last Friday's Beijing Olympics Opening Ceremony, a Chinese dancer fainted, prompting three foreigners to rush to her aid.

The picture of them carrying the dancer has become the talk of China's online community for its depiction of the true spirit of the Olympics, said the English Language China Daily. Thousands have expressed their gratitude to the unidentified foreigners online.

In another case of "goodwill hunting'', thousands of netizens are trying to help track down the father of Olympic 10m air pistol shooting champion Guo Wenjun.

She was abandoned by her father at the age of 14, and when she won the gold medal for her event on Sunday, she said she hoped that the victory might lead to a reunion with her father.

Let's see if the human flesh search engine can rise to these Olympian tasks.