You can recycle it yourself by cutting off the branches and laying them in your garden to protect plants and flowers. While the trunk can be cut up and used in an outdoor fireplace after it has been seasonsed or you can rent a chipper which will chop it up into mulch, be sure to wear personal safety protection if you do. How about cutting the trunk into small slices and making a natural border for a flower bed or glue some cork to the back of the slices for some rustic looking coasters. Have a natural fish pond? Toss your used Christmas tree in to provide shelter and nutrients to fish.
Check with your local town many chip up the trees and use it for mulch in parks; others offer it back to residents for free. Recycled trees have also been used to help prevent beach dune erosion.