Coca-Cola

• If you don't have Coca-Cola, try it with another brand of cola, but just be aware that Coca-Cola specifically has been used to remove rust, as well as other gunky types of build-up, for years. The culprit inside Coca-Cola that is responsible for such powerfully abrasive qualities is the citric acid. For larger rust stains, simply pour the Coca-Cola directly onto the rust. For smaller items, soak a cloth in Coca-Cola and rub vigorously.
  
  

Baking Soda

• Create a paste by mixing baking soda and water. The paste should be the consistency of oatmeal--not too terribly thick. Apply the paste onto the area affected by the rust and let it sit for at least a half hour and preferably an hour or two. Get a scrubbing brush and rub the paste off and the rust should come along as well.
  
  

Vinegar

• Vinegar is an excellent natural way to remove rust from smaller objects like coins and jewelry. Pour some vinegar into a bowl and don't dilute with water. Toss whatever small object you have that is rusted into the bowl and let sit. The amount of time will depend upon the severity of the rust. You can usually see this remedy working within just a few minutes as flakes of rust start to peel away.
  
  

Lime Juice and Salt

• A liberal sprinkling of salt followed by an equally tolerant helping of lime juice on the rusted area can be just as effective as commercial rust-removal products. The key to how much salt and juice to use is to make sure that when you add the juice, the salt doesn't get obliterated. Allow a few hours for this concoction to do its job. Come back with a scrubbing brush and get to work with some elbow grease and the rust just may be completely gone.
  
  

Lemon Juice and Cream of Tartar

• An excellent way to remove rust specifically from stainless steel is by mixing lemon juice and cream of tartar onto a standard washcloth. The citric acid in the lemon has the same effect of breaking down the rust as it does in Coca-Cola, while the cream of tartar turns the washcloth into a more gentle abrasive cleaning mechanism. By using this approach, you can save the stainless steel from the scratches caused by harder abrasive pads.