Ban hits Half-Life 2 pirates hard
About 20,000 people have been banned from playing the Half-Life 2 game.
Game maker Valve shut down the online accounts of the players because it had evidence that their copy of the game had been obtained illegally.
Copies of Half-Life 2 had been circulating on file-sharing systems soon after it was officially released.
Experts said the success of the Half-Life 2 anti-piracy system might tempt other game makers into creating their own version. Half-Life 2 was officially released on 16 November but before gamers could get to grips with the long-awaited title they were forced to authenticate their copy of the game online.
Authentication involved setting up an account with Valve's gaming community system called Steam and letting that check which copy of the game was being run.
