Shepard & Alabama
all damned night!
Also at Kirby & Richmond in the mini-mall and there are 6 other locations I haven't been to (yet).
Cheap, authentic (as far as I know) Mexican food. They have beer and margaritas along with horchata, tamarind soda, and regular American soft drinks. The garlic shrimp and mole dishes are good. There's so much I haven't tried yet.