What you need:
*One or two grapefruits
Cut your grapefruit in half, and coat the halves in kosher salt. You can scrub the salt in with your fingers a bit to saturate it so it will stick.
Scrub the half into a heavily water-stained faucet, or glass. The course salt will scrub off grimy build-up, and the citric acid will eat away water stains leaving a fresh, natural scent.
This works best on metal, porcelain, or glass surfaces. For tough stains, let the juice sit on the surface you are cleaning for about ten minutes after scrubbing.
You can remove water rings in a bathtub, as well as cloudy build-up on glasses and silverware.
(Note: This is for removing stains only, and won't necessarily remove germs and bacteria from dishes. Not a substitute for washing. Don't be nasty.)
Enjoy your shiny kitchen the environment will thank you for!