Other than chipping them up as fake mulch, tires dont have much recycle potential. They do have re-use potential though. Many a tractor and truck tire has been turned into a flower bed. They can be stacked and then back filled / covered to make a retaining wall. Swing as mentioned is a good one.
Good for many types of sports training. Hang one by a rope to throw a baseball / football though to practice. Mount one ot the side of a wall or fence for batting practice - batter swings at the tire making contact with both sides, key is to keep the bat parallel to the surface of the tire. Fill with concrete, with a pole in the middle for portable volleyball nets.
They can be used as "bumpers" to soften hard edges like loading docks.
My granddad would take a tire, put a target in the middle and then roll it across the field - great target practice.
I have several of different sizes filled with concrete to use as ballast and weights for the tractor and disc. I have another with a post mounted to the tire and rim for use as a vise stand.