Chalk in your Tool Box

Tuck Chalk in Your Toolbox to Stop Rust
You can keep the metal tools and hardware in your toolbox rust-free with blackboard chalk. How so? Chalk is a moisture-sucking material that traps dampness. When you place several pieces throughout your toolbox, its porous nature will protect items prone to rusting.

Bonus tip: Got a musty closet? Fill up a small muslin or cheesecloth bag with chalk and then hang it inside. It will absorb the dampness and stinky odor.