I've heard a lot lately that cyclists have begun carrying cell phones with them for numerous practical purposes. Some examples were to call police when being harrassed by motorists, summon medical help when a fellow cyclist was injured in an accident, requesting to be picked up by a friend or family member in the event of a breakdown, and more. Talking on the phone while riding definitely ISN'T one of them.
Do you carry a cell phone while out on a ride? Have you needed to use it for some of the examples above? Do you recommend that cyclists carry one? Please discuss.