According to the Environmental Protection Agency, Americans throw away about 1.6 billion disposable pens every year. The greenest upgrade is to invest in a refillable pen and use that in lieu of disposables. But a more realistic approach is to limit the number of disposable pens you take from hotel rooms, banks or as freebies from promotional events. Also, if markers or permanent pens no longer work, they may not be ready to throw out. Try dipping the tip in rubbing alcohol; this can "undry" the ink and make the markers as good as new again.