Cream the shortening, then add the sugar gradually, beating until fluffy. Add the eggs, then the molasses. Dissolve the soda in hot water, then stir it into the mixture. (Don't beat - to avoid bubbles.) Sift together the salt, spices and 2 cups of the flour. Stir the sifted flour and spices into the mixture. Add the remaining flour gradually until the dough is soft and moist to the finger, but not sticky. Use additional flour as needed. Roll out small amounts of the dough at a time. Keep the rest of the dough cold, including scraps from each rolling. Cut with floured gingerbread men cookie cutters. Bake for 8 - 10 minutes at 350°F. Frosting: Put the sugar, water and corn syrup in a pan and stir over low heat until the sugar dissolves. Boil, covered, about 3 minutes; then boil, uncovered and without stirring until the soft ball stage is reached (238°F). Remove the syrup from the heat. Quickly beat the egg whites (at room temperature) until stiff. Pour the syrup in a fine stream over the egg whites, beating constantly. Add salt and vanilla, continuing to beat until the frosting is cooler and ready to spread. Divide about 3/4 of the frosting into various brilliantly colored batches, reserving the rest for white. Decorate to your hearts content.