This July 4th weekend, kids ruled Chicago. I surrende r it to the little five-year old guy at the dolphin amphitheater at Shedd aquarium, who casually turned, encountered this unbearably cool thing called a prosthetic leg belonging to the cheerful man sitting behind him, and proceeded to spend the next five minutes in wide-eyed, fascinated wonder. His dad looked uncomfortable and embarrassed, but not my little champ. He was trying to decide whether the man possessing a half-metal, half-plastic leg was a super hero. I genuflect before the three-year old girl at the Navy Pier bus terminus who stood her ground against the press of humanity trying to get into the CTA # 66 after July 4th fireworks. There were at least a million people on Navy Pier that day and at least 25% of them lined up to get into the popular # 66. It was an elbow-to-elbow, cheek-by-jowl, survival-of-the-fittest run to the bus. “Hey! Excuse me!” my Joan of Arc protested from somewhere in the region below our collec