Consider listing the carpet for sale in your local classifieds. Your carpet should be cleaned, and in reasonably good condition. Many homeowners are willing to pay for gently used carpeting for their home. By selling your old carpeting you may also help to offset the cost of the new flooring.
Check local nonprofit agencies. Even if the carpet is not nice enough to sell, there are many nonprofit organizations that can put used carpet remnants to good use in their own agencies, or with the families they serve. Check with agencies that serve families and schools. Call local gardening clubs (they use it as mulch) in your area to see if they accept used carpet.
Determine whether the carpet can be reused somewhere else. Find other applications for the carpet by thinking outside the box. Even if your carpet cannot be used as a flooring material, there may be other uses for it. Cut up the carpet and reuse it as mulch, car mats, or in boats, utility rooms or garages.
Recycle old carpeting at a carpet reclamation center. Visit www.carpetrecovery.org for a list of places that will recycle carpet in your area.