Gmail has had this property for a long time and it may be life saver for the ones who does not know it. If the mail you have mistakenly sent is about your business, it may lead you into some trouble. Gmail has an interesting property for such occasions.
You can see this property after logging into gmail.com and clicking “the gear” on the right up of the page, and then select ‘settings’ from the menu and downing the page a little bit to the buttom. This duration is max 30 seconds; you should be aware of your mistakes in 30 seconds.
When you activate this property; you see some choices like ‘your message has been sent’ ’restore’ ‘show the mail’ after sending your mails. It waits you to restore as long as you have set the time for it. At the end of that time period your mail is sent athwart.
Consequently; it may help you to make some changes at the final step or it may help you in the mails that re about to be sent to wrong address.