Amarelinho da Cinelandia
Nosy types like myself can't fail to appreciate the location of this Centro bar and restaurant - the plastic tables and chairs sit right on the flagstones of Praca da Floriana (best known as Cinelandia) - a busy square full of lost tourists, hardworking Cariocas and local loonies. You'll see every walk of life from your seat under the bright yellow canopy, and if you tire of the people-watching there's always the imposing Teatro Municipal to the side of the bar, and the impressive Biblioteca Nacional, right in front. Food is pretty cheap, given the good location, and portions are generally big enough for two. Pizzas are around R$20, a mixed grill with side dishes around the same price. If you just want a light snack and a drink, order a couple of chopps and fries - you'll receive an absolute mound that's big enough for two to nibble on as you watch the crazy goings on in front of you.