I remember one of the few times my brother was ever spanked by my dad. My brother was being horrible, throwing toys, hitting, screaming for no reason, and he was about 8-9, so he knew better. My dad tried time out, nothing, he just kept doing it during time out, and after. He tried taking a valued toy away, nothing. He tried reasoning with him, nothing. Nothing was working, and my brother was only getting worse. My dad finally was at wit's end, and laid him on his knee, raised his hand /really/ far back, and acted like he was going to spank him. My brother kept acting up. My dad then pulled the "really fast, until right before the butt, then stop, and spank really soft" approach (it's about the fear in this one, it sounds fast, but barely hurts at all). It worked. This was the last resort, and my dad was hurt that he even had to do it. There are some times that nothing works.
I'm not saying go out and beat a child, those people disgust me. I'm not saying do it for every case. If a child is just talking back, being sent to their room works really well. I'm saying in the case were a child is not only harming others (toys hit me and my other brother), the child is not listening to their punishment (not doing time out correctly, and leaving their room when sent to it), and when the child is screaming around the house for no reason, sometimes it's the only thing that /can/ work.