Stubb's not only has great grub but they've also got a great line-up of musicians.  Any given weekend, you'll see lines out the door waiting to go in. For music line-ups, check out the local Austin Chronicle or their website.
Their food is also excellent.  Their brisket is very tender but I go there for their chopped beef sandwich.  It's saucy and not as greasy as most other places.  A plus, if you go into their outdoor music state, they have a stand where you can buy a sandwich, chips, sodas and beer while you wait.  Perfect for after-work music.
                        
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