By Jayne Clark, USA TODAY

Fyffe, Ala., celebrates past UFO sightings with its annual UFO Day.

On a February evening in 1989, strange lights and shadows appeared in the sky over the tiny town of Fyffe in northeastern Alabama. The local police department was flooded with calls from witnesses.

The object (variously described as banana shaped or triangular) appeared on subsequent nights, by which time "people were parked on the sides of the roads eating popcorn waiting to see if the UFOs would come back. It was like a parade," recalls Fyffe's current town clerk, Brandi Clayton.

On Saturday, a multitude of flying objects will, indeed, return to Fyffe. Although they'll be of the clearly identifiable variety, like hot air balloons and a military squadron of parachutists.

In a salute to that alien encounter two decades ago, the town of 1,000 or so residents celebrates an annual UFO Day on the last Saturday of August, though it has tweaked the message by dubbing it an Unforgettable Family Outing.

Turns out Fyffe is just one of a handful of U.S. locales that have turned a Strange Encounter into an annual revenue-reaping event.

Most notable, perhaps, is the Roswell UFO Festival in New Mexico, which attracts thousands during the five-day party each July. The town can thank an event in 1947 when a UFO supposedly crashed on a nearby ranch and alien bodies were spirited away for autopsy.

More than six decades later, what came to be known as the Roswell Incident still has conspiracy theorists shrieking cover-up.

It has also spawned a mini-industry of alien-related enterprises in Roswell, like the International UFO Museum and various alien-themed gift shops.

Each May, residents of McMinnville, Ore., throw a UFO Festival to commemorate a 1950 UFO sighting by two residents there.

And in Marfa, Tex., the mysterious Marfa Lights get their own Labor Day Weekend salute in that desert ranching community.

A few months after the UFO sightings in Alabama, the state legislature made what has to be one of the weirdest legislative gestures of all time when it proclaimed Fyffe "UFO Capital of Alabama."

"Some people found it kind of embarrassing and thought, 'Oh, gosh. Are we ever going to get out from under this?' " says Clayton.

Turns out they don't really want to. "Before UFO Day, this town did not have any kind of (civic) celebration," Clayton says.

The free event draws up to 10,000 participants.