There are already hooks in my Interstate on the door posts behind the driver's and front passenger's seats. I put an automotible clothes rod there, mainly because it forces me to duck farther and I no longer bang my head on the front television when going from cockpit to living space. But in addition to providing a guard for the TV, it's a good place to hang a paper towel roll convenient to my galley, or hang spare bath towels. And if I really wanted to, I could hang curtains off of it to divide the cockpit from the living space.
It's not convenienetly situated for hanging clothes, though, unless you hang them between the front seats, which would be kind of in the way.
Engineering: Finding complex solutions to simple problems you didn't even know you had.