A new place opened about a month ago - it's called just "24" and it's at the intersection of Lamar Boulevard and 6th street, where the Waterloo Icehouse used to be. (It's owned by the company that owns the Waterloo chain.)
I've eaten there a couple of times. The menu says breakfast any time - haven't tried that yet. They're trying to make it artsy/upscale food. For example, the club sandwich uses Applewood smoked bacon and blue cheese. It is excellent taste-wise, but they need to use a different bread. The bread they're using now has a crust so hard it gouges the roof of your mouth when you take a bite, and it's so full of voids caused by carbon dioxide when it rises that the bread is likely to break into pieces, which makes the sandwich kind of hard to handle sometime. The macaroni and cheese is too bland.
One really good thing about this new joint is the fact that the parking is still free. Lately, Austin has gone crazy putting in pay-for-parking things. ALL the parking around Katz's is now pay slots. I predict Katz's will fail because of it. Nobody with any sense will pay $6 just to park so they can go to a place that serves 2nd-rate food.