Here's a nice little list covering Sushi etiquette, with which most Americans probably aren't familiar. Some key items:
- Nigiri (a small piece of fish on a small bed of rice) should be eaten in one bite. But if the Sushi chef made it too big to pop in your mouth, don't worry about it.
- Don't mix wasabi into your soy-sauce dish. The chef puts what he considers to be the right amount of wasabi underneath the fish, and you can add a little more on top if you want. Wasabi soup is so gauche (but it's so good I do it anyway).
- Don't leave food on your plate at the Sushi bar. If you didn't want it, you shouln'ta ordered it.