Postal ArbitrageAs of 2025, a stamp for a letter costs $0.78 in the United States. Amazon Prime sells items for less than that... with free shipping! Why send a postcard when you can send actual stuff? I found all items under $0.78 with free Prime shipping — screws, cans, pasta, whatever. Add a free gift note. It arrives in 1 or 2 days. Done.You're not only saving money. It's about sending something real. Your friend gets a random can of tomato sauce with your birthday note attached. They laugh. They remember you. They might even use it!Prices updated 4 minutes ago$0.25Lime$0.42Kool-Aid Unsweetened Tropical Punch Powdered Drink Mix, 0.16 oz. Packet$0.45Amazon Grocery, Brown Gravy Mix, 0.87 Oz (Previously Happy Belly, Packaging May Vary)$0.46Yellow Onion, 1 Each$0.47Maruchan Ramen Noodle Soup, Beef, 3 oz$0.49Lemon$0.50LA MODERNA, Vermicelli Pasta, 7 oz (Pack of 1) | Enriched Durum Wheat Semolina | Kosher, Non-GMO, Iron and Vitamin-Fortified | Thin Vermicelli Noodles for Soups, Broths, and Quick Meals$0.51Simpson Strong-Tie H2.5A H2.5A 18-Gauge Galvanized Hurricane Tie$0.53Amazon Grocery, Tomato Sauce, 8 Oz (Previously Amazon Fresh, Packaging May Vary)$0.56Russet Potato, 1 Each$0.58Apple Barrel Acrylic Paint in Assorted Colors (2 Ounce), 20504 Black$0.77Yoplait Original Low Fat Strawberry Yogurt Cup, Made with Real Fruit, 6 ozIn 2023, I ordered $1 cans of beans to a bunch of extended family members. It ignited our family group chat for a few weeks and everyone was super into it. Pictures of beans started rolling in. Then they started sending random stuff to each other. An asbestos warning label, cookies, a tin of sardines. Someone even sent a pregnancy test to my grandmother. This site is not affiliated with or endorsed by Amazon, obviously!