I made a nice box a few years ago out of 1/2 inch plywood. Love it, nice and very strong... problem is, it's heavy! This year I'm switching over to a plastic box, which is like a small tool box (I got it with a truck I bought several years ago, so I don't know where to get one) (about 36lx20hx20w), which is strong enough to sit on. This box, filled with all my gear, weighs what the wooden box does alone. I use a couple rubbermaid containers with the snap tops inside it to keep my "stuff" somewhat organized. I love the look and stregnth of a wooden box, but I'm becoming more focused on packing as light as I can. I pull the box in a medium size jet sled.
Here is a photo of the box I have (not mine, but from a web site). It's a titan 310000: