Make sure you never lose your way in a strange city. Each of the Knopf MapGuides (more than 30 foreign and U.S. cities, $9 each, www.amazon.com) captures its city's pith in a package as small as a passport wallet, providing six to eight foldout maps, hotel and restaurant listings, subway maps, and information on everything from churches to flea markets. New guides cover Budapest, Havana, Shanghai, and St. Petersburg.