Neat idea for an outdoor tub. I don't think I really want to bathe outdoors (living as close to my neighbors as I do), but I can see using an old tin tub as an outdoor water feature in the backyard. This is at the Magnolia Pearl Ranch in Texas.
Designer Jamie Durie installed this Japaneses-inspired tub in his own backyard so he could bathe under the stars. Built with cedar planks, the unlined tub's joints tighten up when filled with liquid, creating a watertight vessel.