By ERIK ECKHOLM
WASHINGTON � If it is true that, as an old Chinese proverb says, crisis equals opportunity, then the attacks of Sept. 11, 2001, have yielded a bonanza. Billions of dollars have been poured into homeland security by the cabinet department of the same name, the Pentagon, law enforcement and corporations. With so much money available, more than 500 exhibitors at a security conference here last week were out to reap their share.

The most futuristic tools and weapons for tracking and catching potential terrorists were presumably not on display. But if the goods and services hawked at the conference are any measure, the urgent quest for greater security has stirred creative juices among inventors - and marketers.

The presentations included sophisticated equipment like an identity-verification device that reads a finger's unique pattern of capillaries and more mundane items like strong rubber gloves for working at the scene of a disaster.

Mainly a trade fair, the conference was attended by thousands of potential buyers, including representatives from federal agencies and small-town police officers who ogled devices beyond their budgets.