In the rivalry between the two cities, downtown St. Paul’s underdog status has never extended to its Hall of Fame entry in the late-night dining wars. That’s because the Mill City can claim nothing that compares to the we-never-close Mickey’s Diner. Until now, that is. The Nicollet Diner is now doing the 24/7 thing on the north end of Eat Street, cranking out a short-order roster of burgers, malts, deep-fried delicacies and of course breakfast, all day and all night. It may not have Mickey’s architectural panache — what does? — but it’s got its own vaguely nostalgic, soda-fountain-from-the-’50s look. 1428 Nicollet Av. S.; Mpls.; 612-399-6258;