Amazon offers the Fels-Naptha 5.5-oz. Laundry Bar and Stain Remover for $1.09. Plus, Prime members can opt for free no-rush shipping to score a $1 Amazon Digital credit, which can be used on eBooks, digital music, videos, apps, video games, and software. (Non-members can spend $49 or more to qualify for free shipping; otherwise, shipping adds $5.25.) Assuming you'll use the credit, that's at least $2 less than you'd pay at a local store. It's designed to pre-treat stains and is designed to remove grease and oil.