Drunk in charge of a computer? Arrest yourself with a virtual breathalyzer

Called 'Mail Goggles' the application is a product of the fecund, albeit booze-soaked mind of Google Gmail engineer Jon Perlow whose own weakness for late-night, liquor-fuelled missives turned-off one too many potential sweethearts.

Here's how it works. Before a lost weekend, the user activates the Mail Goggles app which blocks emails from being sent during the specified hours unless the reveller can correctly answer 5 "basic" maths problems within a few seconds: if you are too pissed to pass the quiz ­ no email.

By default the app will kick in during prime post-party hours weekend nights to the wee hours.

There has been some criticism (evidently from graduates of the American public school system) that the math problems are too difficult even for sober user to solve within the time allotted.