When Matchstick badges communicate by infrared signal, they give attendees plenty to communicate about out loud. Guests program their badges by answering five multiple-choice questions. As people meet each other, their badge displays light up, showing a green light for each question they answered the same and a red light for each question answered differently. The five questions, customized by the event organizer, can range from the serious to the absurd, as long as each has three multiple choice answers from which to choose.

While the first Matchsticks just shipped in September, the product boasts an impressive lineage: Its protype was created by an MIT student for the 10th anniversary celebration of the school's renowned Media Lab in 1995. The 2 1/2 inch by 1 3/4 inch badges can be rented for $5 per badge, per event (batteries and the programming stations included). To buy the Matchsticks outright, the cost is $19.50 per badge for orders of up to 100 badges, with discounts for larger orders, and $75 per programming station. For more information, contact Fashion Technology in Scottsdale, Ariz. at (602) 991-8246 or visit its Web site at, www.fashion-technology.com.