Have you ever regretted sending an email or fired one off too hastily only to think soon after "oh bother".
Well Google has officially added the Undo Send feature to Gmail. Although it's been available as an experimental feature for a few years, it is only now that it's finally been added to the core service.
Note however that this feature only adds a delay to your 'send' - it doesn't actually unsend a sent email. So by giving you up to 30 seconds from the time you hit 'Send' you can ponder a while and really check that you might have wished to change your mind. It could prove to be valuable thinking time!
To enable the feature - and it really is worth doing, click on the cog in the upper right-hand corner of Gmail and select 'Settings'. Scroll down to 'Undo Send' and you can select the relevant seconds dropdown option. Click 'Save' and you're sorted. Seriously, Do It Now.