To understand why the information technology industry is about to face its toughest period since the dotcom bust, consider the case of 2nd Wind Exercise Equipment, a US company that deals in unwanted treadmills and weight machines.

Tom Kelly, the Midwestern company's penny-pinching head of technology, was faced recently with a $250,000 (£132,500, €167,600) bill to upgrade his company's e-mail system using Microsoft's Exchange software. To save money, he switched instead to Google's online e-mail application, which will cost him $33,000 a year.