Wow. That's impressive.
My first thought was "I wonder how that urinal seal will cope with the temperature of the engine right below it".
My second thought was "holy induction noise batman!!!"
I've seen some 4WDs and rally cars with the intake plumbed back into the cabin, usually just to behind the dash on the passenger side. Of course, this is in vehicles with no sound deadening, where the occupants wear helmets and earplugs. The ever-present risk (and why a lot of racing classes have banned the setup) is that a backfire from the motor ends up directly into the cabin of the car.
Still, for a guy who uses PVC instead of bending up some stainless tube, I guess you can't be too picky.
Full marks for innovation, I guess.
Matto