Though the Great Wall of China has won the accolades of history, the Great Backscratcher of Vietnam, built to reach any itchy corner across the nation, saved more lives than can be counted on a single hand. Feast upon equally ingenious Vietnamese creations with today's Groupon: for $7 you get $15 worth of Vietnamese food from Diem 99 Café.

Diem 99 Cafe serves up a wide variety of dishes, desserts, and drinks. The authentic menu's variegated farescape offers vermicelli, or cold noodle, dishes in varieties like garlic chicken and barbecue pork ($7.25 each), as well as noodle-naysaying rice plates such as the baked short rib and lemon grass mahi mahi ($7.25 each). Vegetarian options are boundless at Diem 99, creating a vast playground of meatlessly delectable obstacles for hungry mouths, such as the lemon grass tofu ($6.97) and tofu curry ($7.25). Cap off a complete, authentic meal with a large banana tapioca ($2.00) and a cup of hot green tea ($1.25) . Ample free parking makes dine-in easy, but feel free to take out for a noodle night in.