Damp Rid - hang these in your closet when visiting a humid destination and your clothes will stay fresh! Pack in your checked bag, watch the water collect in the bag during your stay and then discard before you return home!
Travel Pillow - We love this one as it lasts for years (going on 3!) and doesn’t take up any room in or on top of your bag. Just inflate when you reach cruising altitude and start snoozing.