Austin, Texas TMS

I'm going to in Austin, Texas for about a week later this month for work. I'm not sure how much free time I'll have, but I want to take some time for some good stuff. I'm not staying downtown, I'll be about 10 miles north of there. Probably no rental car, but I can always get a cab.

My main question is what are the best places to eat? BBQ, Mexican, anything else?

Beyond that, if you had time for one thing, what would you do? I've been to 6th street.