I'm a big user of bike-water bottles filled up from my kitchen sink. I even (gasp—germphobe alert!) use public water fountains, and I never get sick or colds. Besides wasting plastic and the resources to truck it to you, bottled water itself can cost as much as $10 per gallon. (That's more than double the price of gas!) Staying hydrated is important—especially in summer—but why drop so much cash when you can fill up at the tap for free? (Spend your buckaroos on fresh berries!)

Tap water is safe in most areas (you can check your local water supply online) and tasty! Want a filter? Try the Brita filter or a Watergeeks sport bottle, which filters out metal and chlorine.

Drinking tap water is not only good for your wallet, it's also good for the planet, because all those disposable water bottles end up in landfills. In fact, SELF writer Gayle Forman, who wrote about reducing her trail of trash, learned that the average American throws out 4.4 pounds of garbage each day. By eliminating bottled water from your life, you can put your trash can on a diet!

And with the money you save on bottled water, you can pick up a bisphenol A–free bottle, like a Sigg, to use over and over again. Plus, keeping a reusable water bottle in your permapacked gym bag is a great way to stay organized—you can rush to the gym whenever the urge to work out strikes.