What is the best way to dispose of cellphones?

Most cities and counties have a local e-waste program. Check your phone book's government offices pages and look for "recycling' or 'waste management". Another good reference is www.earth911.com.

A good company in the United States is All Green Electronics Recycling. They offer free service and have over 100 drop-off locations and do free pick-ups all across the country. Check out www.allgreenrecycling.com or call (800)780-0347