Google Invents Unsend

If you've ever hit SEND and then immediately said oh [expletive deleted], this new Google labs feature is for you. Now you get five seconds to hit UNDO. To install this potentially career-saving feature, go to Settings > Labs and enable UNDO SEND. Needless to say, this only works when you're sending Gmail from the browser interface, not your email client, BlackBerry, iPhone, etc.