I recently returned from a cruise. I found that layering my clothes with plastic bags, like the kind that your clothes come covered with from the cleaners. Or, just plain Wal-Mart bags sandwiched in between every other item, sure will keep them wrinkle free!! IT really does work.
When I finished packing my folded clothes, I had a silk suit and various other hanging things, folded them in half, layed them on top and zipped the case up. When I arrived at my destination, I opened the suitcase and voila' not one wrinkle on my suit or pantsuits. That plastic is a great idea !!!!!