With the growing restrictions and extra fees on checked bags, we use the same approach as mahleu. Just spin off the head and shove it down into a shoe for extra padding, then put the legs in the bag. It requires that we use a bag that's long enough, but it beats paying for an extra bag in the airplane hold.
Edit- You didn't ask the question, but I'll offer this up based on your interest in studio shooting, as seen in other threads: More and more, when we travel to distant shoots we rent lighting equipment at or near the destination. Most major cities have at least one company that rents studio equipment. In almost every case we can rent all the gear we need for less than it costs to ship our own ahead or bring it along as excess baggage.
It sure saves wear and tear on your own gear, too! Remember, there's a ham-handed baggage handler (known by the airlines as ramp rats) that can defeat the most sophisticated packing cases. I swear that they are trying out for ramp rat olympics, the way they abuse bags!