Fogo de Chao is considerably cheaper for lunch than for dinner if you are in the mood to indulge your inner carnivore. Don't know the cost or if all the cuts of meat are offered.
Estia has a number of price fixe lunch specials. Something like 3 courses for $17. Compared to dinner it's a lot cheaper. They also have a fish of the day for $14.
I haven't been there in ages, but Pattaya Grill (40th & Walnut) used to ahve three course lunch specials for $7.95 (how can that be!) that were wonderful.