I love rebar. It's most often used in concrete as a reinforcement, but it has a ton of uses. I've made a fence, a shed, and my future dome home armatures all from rebar. And since it's often made locally from old cars, it's relatively planet-friendly, too, and not very expensive. A 20-foot-long, 3/8-inch thick stick normally costs me about $4. I've purchased more than three tons of the stuff from a metal plant near the El Paso border, about 100 miles from my home.