Gmail's new Undo Send feature

Hey friends, check out Gmail's new Undo Send feature! I think this must be one of the coolest labs features ever added. Remember those times when you got too hyper and clicked on Send too fast or accidentally? Well, with this new feature (you have to activate it from Gmail Labs under Settings), you have a grace period of several seconds to Undo the sending. In a way, this is similar to the recalling message function of Microsoft Exchange. However for the Exchange, one important criterion is that your recipient must not have opened that email... so unless you are sending at an hour when your friend is asleep, tough luck there. Besides, both of you need to be on Microsoft Exchange. So in this aspect, Gmail's new Undo Send feature is better. I don't know how they are doing it but I guess they probably just delay sending for those few seconds till you are "ready". And so, this feature will work no matter what emailing solution your friend is using. I don't anticipate myself using this feature more than once in a purple moon but it is a handy one to have so I have turned it on. :)