The stuff that comes out is pretty gross.

Ingredients:
1 cup warm water
1/4 cup baking soda

Mix the two ingredients and pour into the water reserve of your coffee maker.
Let drip through like a normal cycle minus the filter.
Rinse pot and run 2-3 full pots of clean water through coffee maker.
This will keep your coffee maker fresh and clean!
Recommended use is once a week.