I think this would be such great soap. I love the smell of coffee and it would help to get rid of odors from cooking.
I like the idea of making it in a crock pot and the whole process looks pretty simple. Heart hands home has the tutorial.
Crockpot Coffee Kitchen Soap–Tutorial
http://heart-hands-home.blogspot.com/2011/02/crockpot-coffee-kitchen-soap-tutorial.html