A really cool place in New York City is Beyond Sushi who makes vegetable based sushi. Everything looks almost like chocolate pralines, and it tastes so good!
They also make their own lemonades in several flavors. This is the Cucumber & Mint Lemonade version, not an ounce of alcohol, but still very refreshing.
For a very comprehensive guide on vegan sushi, check out our friends at Keep it Vegan!