You really have to believe in the freshness of your seviche to showcase it like they do at Urbana [3407 Montrose Blvd., (713)521-1086]. The crisp lime-juice marinade -- firmly accented with jalapeños, cilantro, red onions and just a few diced tomatoes -- lets the flavor of the seafood rise to the surface. The dish obviously sinks or swims depending on the quality of the fish, unlike those versions that drown the featured attractions in a murky tomato juice, resulting in a Bloody Mary without the benefits of vodka. Urbana offers huge shrimp, chunks of fresh crabmeat and generous amounts of avocado in a retro soda-fountain glass, surrounded by whimsical red and blue tortilla chips. And at $8, you can also get hooked on the price of this cup of crustaceans.