Like opening an envelope from an eccentric aunt, biting into a calzone can reveal delightful surprises, such as a birthday card written entirely in pepperoni. Munch on tasty correspondence with today's Groupon: for $10, you get $20 worth of calzones at DP Dough Denver.

Working late-night hours stretching from 1 a.m. to 3 a.m., DP Dough Denver's chefs sling more than 30 different varieties of crisp, topping-stuffed calzones spanning classic, chicken, steak, and veggie categories. Calzones ($6.75) neatly improve upon pizza's distinct lack of sandwich traits with handheld incarnations such as the Roni Zoni, which packs pepperoni, mozzarella, ricotta, and parmesan, or the turkey club, a lunchtime revelry of turkey, bacon, tomatoes, and american cheese. Noshers can bite into the bounty of a calzone with pesto, mozzarella, and tomatoes, or dig into a doughy treasure chest of steak, potatoes, and mozzarella. Fully customizable calzones play canvas to ingredient artists, and house-made chocolate-chip or oatmeal-raisin cookies ($3 for three) serve to hide important antique coasters in plain sight.