We've been working with Macey on not touching the dog food. Sometimes when we catch her trying to play in it, she'll quickly point to the food bowl and say "Bad, bad" to the food :)
She learned it from her dog book - there's a "bad dog" in it, so every time we tell Bruce "no" she points at him and says "Bad, Bad!" :) - we do NOT tell her she's bad when she disobeys! (She also tells the computer it's "bad, bad" when she gets caught trying to push buttons)