Twenty thousand people have signed up to participate in the world's largest computer game studio.

Games publisher Acclaim is planning to create a professional role-playing game with the help of the volunteers.

The people, drawn from the ranks of ordinary gamers, will be asked to contribute to the game's art, design, programming and sound.

One of the contributors will be made 'director' of the game, while everybody whose content is used in the final game will be given a credit. The game, known as Top Secret at the moment, will be published by Acclaim when it is completed later in 2007.

The developer is still accepting registrations, but, it says, the entry period will be limited.