Project Baby is the most popular idea his group has ever had. But Frank Guerrero hopes it never actually comes off.

A reward of $US8,000 is offered to anyone who can persuade a large corporation to sponsor an underprivileged child from birth.

The catch: the child must become a walking billboard for the company by being tattooed with its corporate logo - for life.

"It's a bit tricky," Guerrero, one of ®^TMark's organisers, admits. "Unfortunately, our biggest investment ever was for Project

Baby. I don't know what to do about it."

If it ever happens, a widespread howl of outrage denouncing the blatantly unethical nature of the scheme is almost guaranteed.

There's a good chance it would become a hot media topic, serving up the issue of bad corporate behaviour for public debate.

Under normal circumstances, Guerrero and his colleagues couldn't hope for a better outcome - it's just that Frank says the idea that someone might actually follow through with the tattooing makes him uncomfortable.

For the past nine years, ®^TMark (pronounced "artmark") has urged average people to carry out hundreds of projects just like Project Baby. They've devised them, raised money and sat back and waited for someone to come along and take up the challenge - and the cash.

®^TMark funded the now-infamous Barbie Liberation Organization, which switched the voice boxes of 300 Barbie dolls and GI Joe action figures and replaced the dolls for sale on the shelves of a major US toy retailer.

When their new owners got them home, GI Joe chirped "Let's plan our dream wedding!", while Barbie growled "Vengeance is mine!"

The group was also the instigator of the legendary "SimCopter hack" in 1996.

To claim ®^TMark's reward of $US5,000, a disgruntled Silicon Valley games programmer re-wrote the code of SimCopter, a popular computer game, replacing buxom women and other games icons with dozens of near-naked men kissing one another. The games hit the stores and began selling without the change being detected by the company.

More recently, it was the brains behind gatt.org, a very close replica of the official Web site of the World Trade Organisation that, instead of singing the praises of globalisation and free trade, detailed what it saw as the dangers of trade liberalisation.

®^TMark began as an online bulletin board in 1993. "The original BBS was set up as a place for people to trade information, ideas and possibly money for anti-corporate sabotage projects," Guerrero says.

Unlike today, it was anonymous. If a project the group funded was carried out, it wouldn't take responsibility.

Three years ago, it moved to the Web and became an incorporated company with investors and mutual funds.

"The idea was to mimic the stock market in the United States," Guerrero says.

"We wanted to reorient the idea of what investment might mean, expecting a cultural profit instead of a financial profit."

Despite the higher profile, ®^TMark backers choose to remain anonymous and organisers use pseudonyms to protect their day jobs, though Guerrero insists he uses his real name.

The group's financial benefactors are generally aged in their 40s and 50s and are financially comfortable, says Guerrero.

"But they all seem to be people who made their money real quick and in some kind of weird way. One of our main investors made one of those surprise hit movies, an indy film that went big."

The core group of about six people scattered across the US includes teachers and computer programmers and a graphic artist.

There's another very good reason for anonymity: the fear of SLAPP (Strategic Litigation Against Public Participation) suits, a kind of lawsuit that targets individuals rather than the organisation to deter people from participating in an action.

As Guerrero points out, a big law suit would, somewhat ironically, be the ultimate result. "The idea is that eventually some corporation would sue us and therefore put their own corporate rights on trial," he says.

"We pretty much know we'd lose the battle in court, but at least we would be able to try the companies in the court of public opinion at the same time."