The impulse when you hear of the Mall of America is to snicker. And then you stand in front of it bug-eyed in astonishment. So such a place really exists, as lavish and loving a monument to shopping as any cathedral is to God. Within the towering walls are not only 520 shops and 50 restaurants but also a seven-acre amusement park, an aquarium, a speedway, a post office and even a wedding chapel, should the urge strike you on the way to Bloomingdale&rsquos from Macy&rsquos. In 2006, 40 million people visited the mall, moved to travel from as far away as Iceland and Japan by the absence of sales tax in Minnesota. See www.mallofamerica.com.