In a matter of hours yesterday, tickets were going, going, gone for every performance, lecture and demonstration in the Smithsonian Institution's three-day celebration marking the arrival of 2000.

Five telephone lines were "completely swamped" from 9 a.m. on, a Smithsonian spokeswoman said, with many callers hoping to get into several of the free events. The Smithsonian started taking ticket reservations for the programs Monday, and despite scant advance publicity, 5,000 were requested by Thursday evening. The remaining 7,000 tickets were reserved by 3:30 p.m. yesterday.

"I thought it would take until next week," said Richard Kurin, director of the Center for Folklife Programs and Cultural Studies. He professed to be "pleasantly surprised" by the response, saying, "It's hard to gauge the national spirit as to what [this millennial New Year's] means."

No one got preferential or advance service, Kurin stressed. "The fix wasn't in," he said. "There's nothing reserved for my family."

The New Year's weekend program will kick off the morning of Dec. 31 with basketball stars Bill Russell, Chamique Holdsclaw and Nikki McCray discussing their game at the National Museum of Natural History. It will close in late afternoon Jan. 2 at the same museum with musical legend B.B. King singing the blues and talking about them with the chairman of the National Endowment for the Humanities.

Smithsonian officials wanted to hold a much bigger celebration outdoors on the Mall, but budget issues forced them to abandon those plans. The indoor venue, with its more limited seating, means only 565 people can see programs in the Natural History Museum's auditorium, and sessions at the National Museum of American History and Hirshhorn Museum will hold just 270 people each.

A small percentage of tickets for each event was taken out for performers' families, the White House, program sponsors and VIPs, one official said.

The Washington Post Weekend section printed ticket information in a holiday listings box Dec. 3. When reservations opened three days later, 1,900 people called for tickets and those for King were promptly snapped up--even though the schedule did not identify him by name until yesterday. Before that, the sole description referred only to a "legendary bluesman." By yesterday afternoon, even two sessions with speakers described simply as "distinguished panel" were marked "FILLED" on the Smithsonian's World Wide Web site (www.si.edu/americasmillennium / millenniumschedule.htm).

On New Year's Eve, the Smithsonian's activities will precede a celebrity-studded show that will be televised nationally from the Lincoln Memorial starting at 10 p.m. Depending on the weather, organizers estimate the three-hour event could attract 100,000 people. Another crowd will be celebrating on Constitution Avenue NW as part of the city's millennial block party.

Those who phoned too late to get Smithsonian tickets still have a slim chance of getting in. All seats will be filled 10 minutes beforehand, and absent or tardy ticket holders will lose out.

The Web site says that no-shows usually average 15 percent to 25 percent and that visitors should check schedule signs at museum entrances.

As the number of available tickets dwindled yesterday afternoon, callers were less and less selective, said spokeswoman Linda St. Thomas. "People would literally ask for whatever was left."

The topics' unusual breadth--from sports photography to extraterrestrial life--helps explain the public's strong interest, she said. But on the most expensive New Year's in history, "you can't forget the fact that it's free. Everyone else wants $2,000 for dinner."