Google has introduced a Labs feature for Gmail that gives you 5 seconds grace if you change your mind about sending an email.

Gmail users who enable the feature will be able to "undo" sending an email up to 5 seconds after they've hit the fateful "send" icon, for those moments when you realise you've omitted the attachment, or are mailing the wrong "Dave".

In a blog post the feature's creator, Michael Leggett, a user experience designer at Google, explains the thinking behind it:

"An email to the wrong Larry pushed me over the edge. I could undo just about any other action in Gmail - why couldn’t I undo send? ... My theory (which others shared) was that even just five seconds would be enough time to catch most of those regrettable emails".

"And now you can do just that. Turn on Undo Send in Gmail Labs under Settings, and you’ll see a new “Undo” link on every sent mail confirmation. Click “Undo,” and we’ll grab the message before it’s sent and take you right back to compose".

"This feature can't pull back an email that's already gone; it just holds your message for five seconds so you have a chance to hit the panic button. And don't worry - if you close Gmail or your browser crashes in those few seconds, we'll still send your message".