People controlling animated avatar members of a self-proclaimed Second Life Liberation Army (SLLA) have set off computer-code versions of atomic bombs at virtual world stores in the past six months -- with their own manifesto.

The SLLA claims to be an "in-world military wing of a national liberation movement" devoted to replacing the rule of Second Life creator Linden Labs with a democracy representing the nearly four million residents.

"As Linden Labs is functioning as an authoritarian government the only appropriate response is to fight," the SLLA said in a message on its website at http://secondlla.googlepages.com.

"When the SLLA succeeds in its aims it will disband and hand power back to the political wing of the movement."

Creative dissent is welcomed in Second Life as long as it doesn't interfere with the ability of other residents to enjoy the virtual world, according to San Francisco-based Linden.

Second Life said it stopped charging a tax on items created by residents after avatars fashioned in the images of American revolutionaries recreated the Boston Tea Party in the virtual world about three years ago.

The virtual bomb blasts in Second Life explode in hazy white balls, blotting out portions of a screen and battering nearby avatars, animated figures that are residents' proxies in the virtual world.

The self-replicating worm planted spinning gold rings around the virtual world, which is inhabited by more than a million users.

Players treated the attack with a mixture of mirth and anger.

"Can this game get any more unpredictable and exciting?" asked one user, Loretta Lurra on the official Second Life blog.

As users interacted with the rings they replicated, resulting in a slowdown on the servers used by Second Life's creators Linden Lab, in California.

The gaming community calls them "griefers": people who like nothing better than to kill team-mates or obstruct the game's objectives. Griefers scam, cheat and abuse, often victimising the weakest and newest players. In games that attempt to encourage complex and enduring interactions among thousands of players, "griefing" has evolved from being an isolated nuisance to a social disease.

The players of World of Warcraft were left with a similar conundrum in March, when a group of gamers performed an act whose only purpose was to cause emotional pain. The death of a member of the community inspired her fellow gamers to hold a virtual funeral, which was raided by a malicious mob that made short work of the mourners, all of whom had relinquished their weapons as a sign of respect. Since the funeral was naively held in a zone designed for combat, few could question the legitimacy of the attack within the game's rules. None the less, the mourners were outraged, not at the penalties their characters would have to suffer, but at the brazen attack on their feelings.

"I expect we'll see more and more self-government," says Scott Jennings, game developer and author of Massively Multiplayer Games For Dummies. "The reason is fairly obvious if not particularly noble: it's less expensive for game companies to have their customers police themselves than hire people to do it. The trick, and why you don't see it generally, is to construct self-policing schemes in such a way that they don't enable unscrupulous players to use them as tools of grief."

The criminals are trying to rob players of virtual assets obtained in the games, such as 'money' that players can use to buy weapons and goods, according to security firm Panda Software.

Given the effort required to obtain these items, there are many people prepared to pay for them as an easy way to reach higher levels and increase their reputations.

As a result, the virtual economy of the game translates into real profits for the cyber-crook, even more so with new games that allow real-world funds to be transferred into the game for use in the virtual world.

According to Panda, the malware that most frequently affects games are Trojans. In one example the Lineage virus steals player log-in details, allowing another player to steal virtual money to buy weapons, privileges or abilities within the game.

Nimrod Yaffle, a resident of the virtual world Second Life, has revealed details of a bizarre and dark prison Second Life's maker Linden Lab is now using to lock up criminal avatars. Dubbed the "The Corn Field," the moonlit environment contains only rows of corn, two television sets, an aging tractor and a one-way teleport terminal allowing no escape. It exists as an alternative to standard disciplinary measures, which traditionally prevent access to Second Life completely.

After breaking Second Life's rules, Yaffle was informed via email by Linden Lab that he was being sent to The Corn Field. "I thought it was a joke," Yaffle told me in-world. "I never even knew it existed before I went there, and by the looks of it, a lot of other people didn't either." Rumour and speculation about the prison has been running amok in the Second Life community since word of The Corn Field spread, but until recently the prison simulator hadn't been officially confirmed.

"Sometimes when someone is suspended for a short time they are sent to the cornfield," Linden Lab's Senior VP of Community and Support wrote on the official Second Life discussion forums yesterday, adding that building the cornfield didn't require any significant development work and reassuring the community that "Once someone is permanently banned they are no longer welcome in Second Life, anywhere, including the cornfield."