1) Susies Pub
If you are looking for a neighborhood dive that is cozy on a weekday night then this is it. The place is partially underground and Susie acquired it in 2003. It is grandfathered in by a clause that allows the bar to serve until 4a, so after 3a it will fill up from the neighboring dives on Lark street.
The age range for patrons varies widely. I saw couples in their twenties, and dudes in their forties. Overall they've got an attactive crowd, and the place is laid back. They serve liquor and beer, and the beer selection is decent with Guiness, Blue Moon, Sierra Nevada, and local selections on tap. Keep in mind, this is a dive bar, so if you're looking for a well-lit place with nice chairs, and a kitchen: This isn't the bar. For that place, I recommend going to bar #2.
This place is within walking distance from Susies and it is impressive. The food is good and their cocktails are fantastic. The feel is "upscale jazz bar" with an unpretentious atmosphere. You can come in here solo or bring a date - either way you are good. If you do get the desire to mix it up at a local pub, don't sweat it, there are plenty within walking distance.
1) Palmers bar
This is a dive bar. I'm not talking about one of those places that used to be divey and now you stop in for the t-shirt. I'm talking about a no-frills joint that I'm surprised Esquire did a piece on. The place opened in 1906 and when they serve you a drink, you might as well have ordered a double. They're open every day from 10a-2a, and if you're looking for a place with hardcore locals and live music every night: This is it.
2) If you aren't looking for a dive bar and you want to drink great beer, good cocktails and eat awesome comfort food: This is your place. They've won more awards for their handmade German and European meals than there is room to count. Of course, I prefer sitting at the bar over the restaurant: It's just cooler.
St. Louis, MO
1) Some places are described as "warm" without elaborating on what that means. This is one of those places. It's a beer and whiskey joint. I wander in and there's a very good Irish band on stage, with an ample bar to the left and restaurant-style seating on the right. Step down to the bar. The food is better than good. I had a shrimp app that rocked, and if you aren't so much into beer or whiskey, just lean back and enjoy the place. Maybe someone will ask you to share a car bomb.
Keep it weedy!