If you bought a bag of baking flour, say, more than a year ago, there's a good chance that flour has gone bad. Pull it out of the pantry and give it a smell. Does it smell rancid? If so, it's a good idea to toss it. But before you do, go grab the stacks of playing cards you have around the house. Throw the cards into a bag and cover them with the old flour, then seal and shake. The flour will coat the cards and take away the dirt, grime, odors and oils to make the cards fresh and clean. And then take all of the old flour and sprinkle it in the yard, it's biodegradable, and your lawn will love it.