Tortilla Flats has great drink specials and a huge and beautiful back patio. I've eaten here a couple of times and never been overly impressed with the food but it's a great place to get a drink and soak up the sun after a hard day's work.
Also, the servers here have always been very friendly. I went here for a friend's birthday and we split the nachos (which for a Mexican restaurant you think would you been better). I also tried that ridiculous brownie thing (in lieu of birthday cake) and again, I can't say it was too darn tasty. But for some cheap drinks and good times, Tortilla Flats is a good Queen West spot to hit up.