The best place for people watching before midnight in the entire city of Nashville.
The coffee is amazing and pretty cheap, too. I love to sit in there and get a lot of 50 cent refills (cheapest in town!) and be surrounded by interesting culture. The artwork is also locally created usually, and is changed every so often. You'll usually run into someone you know while loitering at Bongo. Their cd player skips a lot and the internet has always worked well, unless you sit in the far back left corner by the window on top of that air vent. It doesn't work there, trust me.