Zagal Madrid, Spain

For some unknown reason, El Zagal—"The Lad"—attracts a massive blue-collar crowd, from electricians and plumbers to construction workers and mechanics. Perhaps the secret is in the televised football games and simple yet delicious Spanish-style dishes; anything with potatoes, meat, cheese, or eggs goes. The daily menu (menú del día) is probably the best bet: for each person, there's bread, a starter, a main dish and dessert. While the décor is nothing special—the entire restaurant consists of a single room with a few wooden tables, walls lined with plain Spanish tiles, and an ordinary bar— the cheap, tasty eats and centralized location are major perks. - Michelle Campagna