I love Mexican food, and I love hole-in-the-wall places. It's hard to find one that has good food AND good service, but La Altena does both. As far as I can tell, there are only about four employees, and they're always working their butts off, but they're friendly, quick, and almost always get your order right. Start off with queso or guacamole (both are delicious), which you won't have time to finish because the food comes quickly. They have standard Mexican fare, generous portions, and even their seafood is reasonably priced. I recommend the Guadalajara fajitas.
Pros: Delicious food
Cons: sometimes crowded