Possible Clues:

• Yen standard in ruins around thousands of Americans rioting
• Symbol of Japan
• Early-morning sight, or a hint to the word that turns up in 17-, 28- and 45-Across
• Japanese symbol
• 1992 Michael Crichton bestseller, and a hint to four answers in this puzzle
• 1992 Crichton novel involving a fictional Japanese company
• [Japan]
• Up-and-coming crappie?
• Part of standard for Japanese students?
• What 'Hitachi' means