Prior to a trip to Europe, a friend suggested packing cubes. I was hesitant at first, as I didn't think there was anyway they could be more effective that what I usually do. Was I ever wrong! I was surprised at the number of items that could be packed into each cube. Folding and rolling the items and then placing them in the cube kept them from shifting and becoming wrinkled once in the luggage. My husband and I packed for a week long cruise in 3 of the cubes.  I put the smallest one in my shoulder bag, and it kept everything contained in one small space without me worrying they'd fall out while under the plane seat. I've recommended to many of my friends.