Why pay Pounds 13,600 a year for Encyclopaedia Britannica online, as a 50,000-user university does under the current Chest deal, when all Britannica's 44 million words are available free at Britannica.com? The publisher explained that the paid-for educational version is free of advertisements, will include a simplified encyclopedia for schools and will be customised for the British education system. The "free" site collapsed soon after its launch last week, overwhelmed by a knowledge-hungry crowd, and was experiencing more access problems earlier this week.