Two now notorious examples of people brought down by email are Claire Swire and Peter Chung, although the former tale is now often claimed to be made up.

The unfortunate Ms Swire was enjoying an intimate conversation with her boyfriend Bradley Chait, a lawyer at Norton Rose in London, about body fluids and their nutritional value. Mr Chait then sent the email to a group of friends, who in turn passed it on. It was sent around the world within hours, although the people involved later claimed to have been set up and that the conversation was a hoax.

Peter Chung was a New York banker posted to Korea who boasted of his active social life, prowess with women and how he would create a "harem of chickies".

He was sacked by the well-respected investment organisation, the Carlyle Group, as soon as the email became public.

Those may be extreme examples, but show how a careless email can cause problems.