Virtual world Second Life had to close its doors for a short time on Sunday after a worm attack called grey goo.
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.
Second Life has become one of the most talked about developments in cyberspace in recent years.
Companies are taking note of these digital realms, 3D worlds populated by onscreen representations (avatars) of real life people, as they gain more and more popularity.
Adidas, Reuters and Channel 4's Big Brother are just three real world commercial enterprises setting up business in Second Life.
Second Life has a population of more than 1.5 million and Linden Lab, its creator, says it is growing at about 38% every month.
The inhabitants can buy and sell virtual land and objects for real money and in any 24-hour period as much as $690,000 can be spent.
But the grey goo attack and recent controversy over a tool called copybot which can be used to replicate people's virtual wares without paying for intellectual property rights is beginning to sour some people's opinion of the world.
Second Life is filled with user-created buildings and objects
One user, Marzipan Maladay, wrote on the official Second Life blog: "Congratulations Linden Lab, you've finally done it.
"I'm selling my land since I haven't been able to use it for nearly a month. I'm sure I'm not alone in declaring that this is last month you are getting [money] out of me.
"Maybe you can con the new people into believing that this is a great thing but you can't fool the people who have been here any length of time.
"You are selling a service which you can not and have not been able to provide."
Some users are angry because the copybot tool can be used to make replicas of objects created in the virtual world and sold by some users in their virtual shops.
The shopkeepers pay a monthly fee to Linden Lab for the virtual land where they keep their shops.
Copybot was originally intended to be used as a tool by Linden Lab to find vulnerabilities in the virtual world but it has since been modified and spread to other users.
Linden Lab has promised it will release tools to protect people's virtual assets in the first quarter of 2007.
"Like the world wide web, it will never be possible to prevent data that is drawn on your screen from being copied," the company wrote in its official blog, advising residents to sue those who are copying their wares.
Other users are unhappy that Linden Lab continues to offer free accounts to people, who are portrayed more as sight-seers than real residents and increase the load on servers, diminishing the virtual experience for everyone else.
"Stop admitting new residents to Second Life until you get adequate server power," wrote one resident on the official blog.
Users complain that the virtual world becomes unusable once 15,000 people - a fraction of the overall residents - are logged on simultaneously.
No-one from Linden Lab was immediately available for comment.