What's a good go-to slow cooker recipe?

Smitten Kitchen has a blow your face off good and spicy brisket: 

http://smittenkitchen.com/2010/01/southwestern-pulled-brisket/

Any chili is a great leave-it-and-let-it-cook option! I usually prefer turkey chili, like this one:

http://lowfatcooking.about.com/od/dinnerrecipes/r/turkchili1104.htm

And the best part is that you can really add in any ingredients to switch up the flavor each time (veggies, spices, condiments, etc)!