Softopper. I don't like caps on trucks - they limit cargo carrying flexibility, I don't like the way they look and they don't play nice with a fifth wheel. But, when you need a cap they're pretty much indispensable. When we go on a family trip without the camper I throw on the Softopper and we've got a huge enclosed cargo area that we pretty much fill.
I don't recall needing so much $hit when I was a kid but mine don't pack light. Multiply that by three and add my wife and dog and that's why we take the truck on those family trips.