Lesson 1. If your crock pot ever ends up looking like this, use baking soda and water.
If your BBQ Chicken ends up a little overdone (as in black sauce) you probably shouldn't waste a lot of muscle power trying to scrub it. Let it soak overnight in soapy water instead. When you wake up in the morning and it still looks the same, you might decide the best solution is to do a Google search on "how to clean burnt crock pot". Don't be fooled by the claims of boiling vinegar water in the crock pot for a few hours. Don't even think about wasting a dryer sheet by letting it soak overnight in the crock pot. Instead, just add water to your crock pot past the burnt line, stir in a few tablespoons of baking soda, and let that solution boil for a few hours. The burnt stuff will float right off, leaving your beloved crock pot good as new and ready to cook up your favorite recipes on low for 6-8 hours as usual.
Lesson 2. It's a very good idea to never leave anything on the stove (except for a pot).
Hypothetically speaking, you should probably never leave a plastic measuring cup on the stove because you might turn on the wrong burner when you're making rice for dinner. And you might get busy putting laundry in the washing machine, with two little girls eagerly pulling on your leg so they can help throw the clothes in the machine. And as the water is running in, you might start to wonder what you're smelling: Could the washer be malfunctioning? Is the rice boiling over?
You might be shocked to discover a smoking something on your stove (the cup is beyond recognition now). While you stare in surprise at the stove and your kitchen fills with smoke, you might start yelling for your husband. You'll probably come to your senses enough to turn off the stove and herd the children out of the house, while your gallant husband scraps off the stinky mess on the stove.
You might even be lucky enough to have your house smell like burnt plastic for a few days! Don't hesitate to pull out your arsenal of scented candles to mask the smell, and be glad you live in Florida where you can open your windows and doors really wide in the middle of March.
And just be thankful that nothing more was destroyed and nobody was hurt. :)