This $6 Bathroom Staple Saves Me Money Every Day

I'm hardly a beauty product junkie, but as I've gotten older and more conscious about the ingredients I'm using on my skin, I've shifted from buying drugstore brand products to more higher-end, eco-friendly, and natural brands. And they don't come cheap. So when I've spent almost $100 on a skincare product (I'm looking at you, Drunk Elephant's Glycolic Night Serum), I want to use it until the last drop.