One thing I've noticed in this thread is that no distinction is being made to the age and development of the child.  Just for the record, "time out" is equally as ineffective as "spanking" on a toddler and most preschoolers.  Distraction is what should be used and POSITIVE REINFORCEMENT when expected behavior is observed.
		
		
	 
Sure, it's best to avoid conditions which might produce melt downs and tantrums in toddlers.  I was pretty good at this but once in a while, someone had an unanticipated meltdown or one which was due to unavoidable circumstances (who knew son would become so attached to the firetruck he ignored the day before and melt down when I put it away in the closet?  Two year olds are not rational in the same way most adults use the term. ).  I found removing the child from the situation or simply to a quiet place to allow the child to calm down was far more effective than trying to 'distract' the child.  Sometimes with rocking, soothing, sometimes just quiet.   Some would term this 'time out' but I never used that term with my kids myself.  
Here's the thing: our job as parents isn't to make certain that the road of life is always smooth and trouble free, with no bumps or bruises along the way.  That's an impossible task and performing it very well actually cripples the child and makes the child unable to tolerate or overcome or even flourish in the face of adversity.  Let's face it: we all face some adversity.  Our first shot at handling it should not come our freshman year of college.  And trust me: there exist parents who would prevent even that trauma from harming their little darlings.
Our job is to teach our children to handle life's little bumps and bruises and learn from them so that they will be able to handle what life throws at them, and even flourish in the face of adversity.  This is called resilience.  It is a good thing.  Essential, actually.
It is also our job to teach children that their needs are not the only ones which exist and not the ones which are most important most of the time, that it is highly desirable to be able to look at the world from the point of view of other people, to do the best job we can possible, to accept ourselves while striving to be better people, to accept other people without necessarily taking their bullshit or throwing out more bullshit of our own.  That honesty and kindness are essential.  To try to leave the world a better place when we leave it, starting with our rooms and first apartments.. and so on.