After looking at stitch and glue boat construction, I've often wondered about taking some sheets of construction foam (the blue stuff), cutting it to form the sides of the box, stitching it together at the seams to form the box, and then covering it with a layer or two of glass/resin. Should make for a not too heavy and stiff box (that could also make a great cooler) that isn't too hard or expensive to put together.



As it would float, you could hop in it and paddle it around as well...