Here are my favorites.
A good beef roast. Throw it in with some pepper rubbed on it. Add mixture of beef broth and water to go about 1/3 of the way up the roast. Fill the rest of the crock pot up with baby red potatoes, baby carrots and onion quarters. Cook on low for about 8 hours.
I make a chicken wild rice dish that is soup and some more rice and mushrooms added to thicken it up. Line the entire top with chicken breasts and let cook on low all day.
My last one is a roast beef chili. Start off with tomato paste and beef broth. Add whatever you want for beans, corn, etc (stewed tomatoes, corn and jalapenos are awesome). and add a pound or two of raw cubed beef roast. Let it cook all day on low.
My kids's favorite is a cook a big package of chicken drummies in barbecue sauce mix sauce all day. Very simple but they will devour those things.
Haven't made it yet but just had some little smokies that were cooked in a sauce that was made of beer, grape jelly, and something else. Mother in law is sending me the recipe as they were awesome.