Skip the bottled water.

* Not only is bottled water expensive, but it generates large amounts of waste. In the United States, the Earth Policy Institute has estimated that the process to make the plastic for water bottles burns 1.5 million barrels of oil, which could power 100,000 cars for a year. This is made even worse when you realize that 90 percent of the plastic bottles are not recycled and sit in landfills where they will slowly decay for centuries.

* Use a water filter to purify tap water instead of buying bottled water.

* Bring a reusable water bottle, preferably aluminum rather than plastic, with you when traveling or at work.