Zhang Shihe is not your typical activist. But the 57-year-old retired Chinese advertising executive has embraced the role since rescuing 14 disabled people from the streets of Beijing, thanks in large part to the power of his blog.
In the winter of 2007, Zhang wrote on his website about the desperate living conditions of those left behind by China's booming economic growth -- the homeless people he met on the pavements of the capital.
The reaction in a country where more than 380 million people now surf the web was generous and immediate: donations poured in.
A year later, Zhang was able to find housing for them in Daxing, about 30 kilometres (20 miles) outside the city centre.
"The phenomenon of homelessness reflects a certain failure on the part of the government and is therefore a sensitive issue," he says.
In China -- a country of 1.3 billion people where the social safety net remains unreliable, and the options for the homeless are limited -- people are becoming more aware of the dire conditions in which many are forced to live.
Although they received little coverage in the media, the deaths this winter of two homeless people in the capital were nevertheless widely criticised on Internet discussion forums.
There is no official tally of homeless people in China's capital.
Some are poor and disabled, and come to Beijing to launch complaints against their local governments. Others are migrants in search of work.
But they all sleep rough, preferring to brave temperatures that have often plunged this winter to -15 degrees Celsius (5 Fahrenheit), rather than face the prospect of staying in one of the capital's 18 shelters.
Wang Yuhai, a one-legged 48-year-old who has benefited from Zhang's assistance, risked it once.
"It was like a prison. There were 10 of us in one small room," he said.
"I was even beaten by one of the guards".
The homeless also face the danger that they will be forcibly sent home from the shelters.
"In general, homeless people, the majority of whom come from other parts of the country, do not opt for this solution," explained Tang Jun, a researcher at the Academy of Social Sciences.
"After a few days, they are either returned to the street or escorted by force back to their hometowns," he said.
"But it's a pointless exercise -- sooner or later, they come back."
Wang, whose mentally-disabled wife followed him to Beijing, does not want to return to his home in the northern province of Hebei, where their three daughters are being raised by friends and relatives.
He and the others helped by Zhang are no longer begging to stay alive. They work as hawkers selling maps in a tourist area of central Beijing.
On a good day, they can each earn 10 yuan (1.50 dollars).
On weekends, Zhang comes to see them, armed with food and clothing.
"Web surfers from across China send us these things," he says.
Zhang does not want his help for the homeless to become something broader and is not interested in establishing a foundation of any kind, preferring instead his discreet, private acts of charity.
"I have no organisation and I'm not a protester. I know what the authorities can tolerate and though they are sometimes irritated by what I do, I have never been seriously harassed," he adds.