Being able to see properly is an important part of health. Unfortunately not everyone can afford to buy themselves proper glasses. Just like used clothes or sneakers, you can donate your used glasses. LensCrafters, Pearle Vision, Sears, Target, Sunglass Hut, and BJ's Optical all donate used glasses to Give the Gift of Sight, a program that gives glasses to underprivileged people in North America and developing countries. All you have to do is drop your old glasses off at one of the locations and the program collects, cleans, repairs, and catalogs them into a computer system so they'll be properly donated to someone who'll be very happy to be able to see them.
For more information, check out GivetheGiftofSight.com.