If you use Gmail for personal or business, I recommend enabling the “Undo Send” feature in your labs settings. It flashes a bar where you can cancel sending your message for a few seconds which really helps, since apparently, it is normal brain function to only remember that one little thing after you have clicked send.
I have a theory on it, though. We likely have a small rush of adrenaline each time an email is sent that triggers a moment clarity in thought the moment we “pull the [send] trigger”. I haven’t had a crazed moment like Bridgestone’s new commercial (yet), but it has saved me some minor heartache.