At 4:06pm on 14 August, hundreds of law firms got the unwelcome chance to test their disaster recovery plans as the power, lights, and computers went off almost simultaneously for 50 million people throughout the northeastern US and Canada.

Some IT departments scurried to find their Y2K plans and checklists. Many others got their first chance to test new plans and infrastructure that they had put in place following the 11 September, 2001 disaster at New York’s World Trade Centre.