Photo: Nikada/iStockphoto

Shop sustainably.

The nonprofit Climate Counts (funded by organic yogurtmaker Stonyfield Farm) rates companies on a scale of zero to 100 for their efforts to halt climate change. If you're out shopping and want a company's score, simply text "cc" and the name of the company to 30644 to get the Climate Counts rating.

Hit the right note.

Why settle for a mere brrnnng when your phone can chirp like a Gila woodpecker or giggle like a panda bear? Visit RareEarthTones.org to download free ringtones reproducing the sounds of these endangered species and more, courtesy of the Center for Biological Diversity. And if the ghostly song of the humpback whale makes people look at you funny, seize the chance to talk up the center's work to save species from extinction (BiologicalDiversity.org).

Waste not.

If you have an old cell phone gathering dust in a drawer, you're not alone: Some 100 million phones languish unused in the United States, and recycling them would conserve enough energy to power nearly 200,000 homes for a year. To find out more, or to learn how to recycle yours, visit EPA.gov/cellphones.