Given that there's a big, unused cavity under the seat, has anyone come up with a suitable "container" that would fit inside there? I thinking of something that would hold a few small items like zip ties, roll of electrical tape, small collapsible backpack or bungee net. It doesn't have to be water tight - a gallon Ziploc(tm) freezer bag would make a good liner. It would almost have to be made of something soft like dense, closed-cell foam to keep it from rattling around. Or maybe something rigid with foam padding.