"Unsend" your mail

Have you ever hit the "Send" button only to regret it a few seconds after?

With Gmail's newest feature, you can "unsend" your mail. It is still a Gmail Labs feature, so you need to enable it. Once enabled, you now have 5 seconds to hit "Undo" before the mail is sent on its way. You may extend this to up to 10 seconds.

However, you now have less excuses for sending inexcusable mail, especially with Mail Goggles as well.