Rubbermaids make good nest boxes... high humidity hides as well for larger animals. I use them for pretty well all of my monitors to hide in. My timors have aboreal small 5 gal rubbermaids to hide in full of moist sphagnum moss, works well.
Remember, high humidity to us is still moderate to most herps. even the most dry conditions are usually still humid as most animals seek refuge from dry heat. A heat lamp on a rubbermaid (using screen melted too the lid) would suffice for leos easily, as the area surrounding the lamp or UTH will be dry, and the unheated area will be moist.. Good way to create a mini weather system.. give the animal choice.