Does your garbage disposal smell like last night's dinner?  Here's a recipe to kill odors and keep your disposal fresh. Flush your disposal with a mixture of water and ½ cup baking soda once a week.  You can also grind citrus peels for a clean, fresh scent.  NEVER use harsh commercial drain cleaners - they'll harm the machine.  It's much safer to use the natural alternatives - they're inexpensive and right at your disposal.