Local Frisch's restaurants are celebrating the birthday of founder David Frisch with a day of free food on May 3. Frisch opened The Mainliner in 1939, the area's first year-round, drive-in restaurant. Nine years later, he opened Big Boy on Central Parkway. To honor his birthday, dress up like Big Boy — checkered pants/overalls and all — and get a free Big Boy platter; come partially dressed, get a Big Boy sandwich. The offer is only available for dine-in customers. A printable costume is available here.