On my floorboard, directly under my feet, I have a deep ribbed rubber floor mat, from a local auto supply store. Point being, any melting snow, mud, whatever, doesn't migrate back to the tail cone but stays on the mat. It probably holds half a qt. of fluid. I can judge how much fun I've been having by what's trapped in the mat.
Glued to the inside of my fabric plane, as an interior finish, I have DASH MAT bulk carpet, it weighs nothing, and just happens to be (or if not, close enough) the loop to Velcro's hook. So anything you want to stay handy, put some hook velcro on it and there ya go.