I'll add the Pedernales River to that list as well. I had a "foreigner" ask where to fish in the Peddernails river for white bass.
Good one, too!
I spent a lot of time in Louisiana as well, so while not strictly Texas only, here's a couple of extra credit items:
1. While most here can probably pronounce Nacogdoches (Texas) correctly, how do you pronounce Natchitoches (Louisiana)?
2. What is the difference between a "jackass" and a "coonass"?