In the second of three reports for the Six O'Clock News from South Korea, BBC News business correspondent Rory Cellan-Jones writes about the virtual lives many South Koreans are living via the net.
In a 10th storey apartment with a stunning view over Seoul, Woo Jae-yeon is explaining how she furnished her room.
Koreans are keen on being connected at all times
"It was a bit bare at first," she says, "so I bought these bright colourful carpets and the flowery wallpaper. And these pictures of a Disneyland Castle represent how I want to live - like a Princess."
This professional woman in her mid-twenties isn't describing the tastefully furnished apartment she shares with her husband - but a virtual room on the internet.
Jae-yeon is among 17 million Koreans who spend a lot of their time in Cyworld - a website which provides them with a virtual social life.
Anyone who signs up gets a homepage, featuring a so-called miniroom and an avatar - a miniature representation of themselves.
The room is bare - and to furnish it they pay a fee for every new virtual item. Then it becomes a vital part of their lives. They link up with friends who have Cyworld minirooms, post photos on the site of everything that happens to them, and then spend countless hours visiting each other in cyberspace.
One in three South Koreans has a Cyworld membership and amongst people in their twenties the take-up is 90%. Jae-yeon says even her mother has signed up - and leaves messages for her daughter on her Cyworld page every day.
At Cyworld's headquarters, 3,000 servers handle traffic for the virtual world in a control room fit for a space mission.
Some fear gamers are spending too long in cyberspace
The business is profitable - with most of its revenue coming from selling all that virtual furniture - and is expanding into China and Japan. "We have a new word in Korea" a manager tells me proudly - "Cyholic - for someone who is addicted to Cyworld."
But some Koreans may be spending a little too much time in cyberspace. In one of Seoul's cyber cafes, row upon row of people packed together like battery hens play endless online games.
The manager told me some players spent days here.
Kim Sae Ju, an unemployed man in his early thirties, broke off from his game to tell me that he spent around six hours day at the cafe. So - why is it so compulsive? "You can get satisfaction from your cyberego that you can't get from the real world," he told me.
For the best young players it can also be the route to fame and fortune. In a packed TV studio I watched with some bemusement as a crowd oohed, and aahed, moaned and cheered.
On a stage two young men battled each other at the strategy game Starcraft. They were impassive - the crowd anything but. The game was being televised for one of two channels which show nothing but computer games 24 hours a day. As the contest ended, some of the teenage girls who'd come to support the losing player were close to tears.
There are a few misgivings in South Korea about this obsession with the online world - at least two people have collapsed and died after playing computer games for days without a break, and youngsters have been caught stealing money to pay for virtual goods.
The net has become vital to many Koreans way of life
But young Koreans are now so accustomed to running their lives via the internet that they find it difficult to conceive of how life would work if the technology wasn't there.
Back at her apartment I asked Jae-yeon what would happen if the internet crashed and she couldn't get to her Cyworld miniroom. "For how long?" she asked, a wave of panic crossing her face. "I just don't know how I would cope."
You can see the second of Rory Cellan-Jones' reports from South Korea on the Six O'Clock News on BBC One at 1800 BST on Wednesday.