By Alfred Hermida BBC News Online technology editor

Wash virtual windows on your TV screen

The EyeToy is a novel controller for the PlayStation 2 (PS2) which uses body movements, rather than a joypad to play a game.

The camera, which comes with 12 mini-games, has sold more than 250,000 copies according to unofficial figures since it was launched in Europe a month ago.

"It draws in so many people that don't normally play video games," said EyeToy developer Ron Festejo, "within five to 10 seconds you know how to play."

Party on

The appeal of the EyeToy lies in its simplicity. Instead of relying on a traditional pad with a myriad of buttons, the games with the camera are all controlled by movement.

The EyeToy itself is a small camera that plugs into a USB port on the front of the PS2 and sits on the TV facing you.

It is very different to what we are used to and suggests that thing that are new and quirky will be successful Adrian Drozd, Datamonitor analyst

The camera then watches you and, based on your movements, different activities can happen on the screen.

It uses motion-tracking technology which was first developed by Sony in the US three years ago.

But it was up to developers in London to turn the research into a new way of playing games on the PS2.

"We thought about what we could do with motion-tracking and came up with the idea for little party games," Mr Festejo told BBC News Online.

"With this technology, we're going to teach the world to clean windows," he said, referring to one of the games called Wishi Washi which involves cleaning windows by waving your hands.

The aim of the team was to create a new way of playing games that would have universal appeal. Many casual gamers are put off by the increasing complexity of the controls of many of today's new games.

Instead London Studio wanted something that anyone could play, regardless of age or ability.

"I wanted it to be a broad experience," explained Mr Festejo. "I've been saying that I wanted to make a game that a person of three to 103 could play.

"The oldest person who has played the game is 90, so I'm not far off."

The games are all designed to be easy to pick up and bring a smile to your face.

"EyeToy follows various other kind of party parlour games in which part of the fun is to actually embarrass yourself," said David McCarthy, deputy editor of gaming magazine, Edge.

"These games are not designed to be played in solitary confinement but with your friends."

Bestselling gadget

The EyeToy has proved such a success for Sony that it even toppled the new Tomb Raider game from the top of the UK games charts.

EyeToy games designed to have wide appeal

"It has captured the public's imagination," said Adrian Drozd, managing analyst at Datamonitor, who has an EyeToy at home.

"It is very different to what we are used to and suggests that things that are new and quirky will be successful."

Part of the success, though, is due to the cost of the EyeToy. It retails in the UK for the same price as a normal game, meaning that Sony is effectively subsidising the cost of the camera.

"The price point is relatively low," said Mr Drozd. "It is not like it costs �100, so it is not expensive and can be just an impulse purchase."

"And low cost peripherals are a good way of extending the life cycle of a console."

The developers of the EyeToy believe peripherals like the camera will become standard on future game consoles. They are already working on a music game for later this year and say that others are interested in creating games for the device.

Further down the line, they see the camera going online, offering people the chance to compete against others the world over. It could also be used for video-conferencing, as the camera has a built-in microphone.

"It is a very versatile piece of kit," said Mr Festejo, "I wouldn't be surprised if Nintendo and Microsoft bring out something similar."

The EyeToy is due to go on sale in the US in October, though no date has been set for its release in Japan.