Last week, I read that an estimated one billion cell phones are sitting around people’s homes, gathering dust—and bound to end up in the trash when you get fed up unearthing them during your annual spring cleaning. LAPTOP has been riding the green wave for a bit now, so in honor of Earth Day 2008 (that’s today, kids), collect those old phones and check out the following donation options to ensure the only impact your retired handset will have is a positive one. Collective Good: Select one of more than a dozen participating charities and organizations (including the Human Society and American Red Cross) to donate your old phone. Shipping costs are tax deductible. Motorola Race to Recycle: Schools and companies can sign up to collect old phones, including PDAs and smart phones, to raise money for their respective institutes. The Race to Recycle Web site includes a list of hundreds of handsets and how much participants will receive for each model, ranging in amounts from 23 cents to $63. Nokia: The green mobile-tech leader offers a phone-recycling service, to which users can mail their old (Nokia and other) phones for proper recycling and disposal. Go to the site, fill in your info, and print the postage-paid return label to ship your old phone—at no cost to you. Verizon Wireless HopeLine: Bring your old device into any Verizon Wireless store for donation to domestic violence victims and shelters. The proceeds provide cell phones and cash grants to these organizations; the service also provides environmental disposal of unusable devices. Before donating or recycling your phone, don’t forget to erase your data. Recellular.com offers help on how to wipe your cell clean. Check out more tips from LAPTOP for buying green.