Maybe time for somebody to compile a list of wipe-clean, liquid-proof e-readers?
Travel sickness pills certainly solves the reading problem for me; I become so drowsy that any kind of intellectual activity loses its allure.
However, one thing that does work against motion sickness in my and many other cases is keeping your eyes on the horizon. Thus a technological solution suggests itself: Use the accelerometers in a tablet to keep the text still,
relative to the ground. Test pilots wanted; wipe-clean, liquid-proof tablets recommended.