This story hit The Register today. An ex-employee planted a program called a logic bomb that would remove data from a companies server on a pre-programed date. What is most striking about the story is number of servers that could have been effected 5,000! That would have taken a lot of work hours to bring them all back on line.

Its not the first time that a company has been effected, a previous logic bomb effected over a 1,000 machines when it went undetected.

The moral here is have a backup but also make sure that only approved people have access to your sensitive information.