Have you ever sent and email and then realized a second later that you forgot an attachment or didn’t include some information? We all have. To help with this problem, Gmail has introduced a new add-in from their Labs section appropriately named ‘Undo Send’:

Oops, hit “Send” too soon? Give yourself a grace period of a few seconds to cancel sending, then edit your message before sending again.

To add this to your Gmail account, click on the Settings link and then go to the Labs tab. Scroll down until you find the ‘Undo Send’ option and enable it. Once you do this, after you send a message you will see an undo link above your inbox for a few seconds which lets you recall the message you just sent.

Definitely a very handy add-in.