The technology would make computer games more engaging, too.

ECONOMIST: Facial monitoring

Another example of the closing gap between the worlds of gaming and grown-up simulation is the decision in May by Digital Sandbox, a supplier of simulation software to America's defence department, to set up a consumer division to make computer games.

ECONOMIST: Serious games

Then the big boys with global licences arrive: Lego to make construction kits (build your own Hogwarts castle), Mattel to make Harry Potter toys, and Electronic Arts computer games including, finally, a chance to play the obscure game of Quidditch (a bit like an aerial version of polo, but with the contestants flying on broomsticks).

ECONOMIST: Harry Potter and the publishing goldmine

Other games have used AI to make a computer-controlled opponent harder to beat by letting them cheat.

BBC: Creature from Black and White Electronic Arts

They can surely put on a pair of glasses to make it even more special. 3-D computer games should appeal, too.

ECONOMIST: Who needs it?

Game makers are turning to AI to make titles stand out in the highly competitive world of computer games.

BBC: Creature from Black and White Electronic Arts

Students can easily take notes in class, children can play games, artists and designers can make sketches or draw directly on their computer screens and the corporate user can answer emails or work on a spreadsheet as they move between meetings.

ENGADGET: N-trig's Digital Pencil plays pen and fingertip roles, claims mastery of both