Once upon a time, duct tape was used for a practical purpose - fixing ducts - not for making prom dresses or toe rings or sculpture.

But that was before duct tape moved out of the toolbox and into pop culture.

For reasons that may well be inexplicable, there has been a spontaneous eruption of duct tape expression in North America in the past few months.

For example, an American flag the size of an NBA basketball court, made completely of red, white and blue duct tape, was unveiled this month in Manhattan's Union Square to commemorate Flag Day. It was made by full-time duct tape artist Todd Scott.

Last month, Holly Monsen of Palermo, Maine, was one of hundreds of high school seniors across the country who showed up at senior proms in a homemade duct tape gown, as part of a contest sponsored by Duck duct tape. (She chose a lacy Victorian theme, rendered carefully with a precision knife, and her date wore a matching duct tape tuxedo with cummerbund.)

At least eight books of duct tape humor by various authors have been published recently, including Duct Shui and Ductigami, which explores the art of duct tape folding to create such objects as a toilet roll cover and cell phone holder. A 2002 desk calendar offers 365 uses for duct tape, as in: "Lose your pooch? Duct tape a pork chop to your chin."

Also, a full-length duct tape movie - Red Green's Duct Tape Forever, about a duct tape virtuoso who lives in a fishing lodge - has recently been released in Canada and opens in U.S. theaters this summer.

In short, "you are seeing a groundswell movement of people who are duct tape fanatics," says Bill Ryan, marketer for 3M's Scotch duct tape.

The questions are: Why now, and why duct tape and not, say, two-sided tape or masking tape? After all, duct tape is hardly new: This year is its 60th birthday.

Duct tape, a strong, three-ply tape made of polyethylene, fabric mesh and rubber-based adhesive, was first manufactured for the U.S. military during World War II by the Johnson and Johnson Permacel Division, according to Tim Nyberg, a Minneapolis graphic designer, co-author of Duct Shui and four other duct tape books, and de facto duct tape historian.

Originally, the tape was used to keep moisture out of ammunition cases, but the military also found it useful for fixing guns, jeeps and aircraft parts.

After the war, it was used in the growing housing industry to connect heating and air conditioning duct work. But it soon became clear that because it was so sticky, tears easily and conforms to various surfaces, people were becoming "very emotionally involved with duct tape," Ryan says.

For one thing, "it has saved a lot of people in a lot of situations," says Scott Sommers, senior category manager for Duck duct tape, one of about eight companies that manufacture duct tape. It's been used to hem dresses; fix holes in car upholstery, tires and radiator hoses; repair trees and shoes; patch tents; and protect windows in hurricanes. It's rumored to be used by fashion models and beauty pageant contestants to enhance certain body parts.

Nyberg knows of a dog owner who used duct tape on his Doberman's injured foot and a weight lifter who wraps his shins with duct tape to protect them from the weight lifting bar. Duct tape has also been used by NASA astronauts to do repairs in space.

"I'd venture to say that 90 percent of homeowners have at least one roll somewhere in their house," says Dan Lynch, a Bellingham, Mass.-based spokesman for Home Depot, where duct tape sells for $4.97 for a 45-yard roll. "I just used it this morning to tape together six or eight pieces of copper tubing so they wouldn't rattle around in my car. Right now, I'm watching my wife on the porch, while the tablecloth on the picnic table is flopping around. Eventually, she'll get the idea to duct tape it down."

"It's a universal panacea," says Nyberg, who is half of the duct tape author-and-comedy team called "Jim and Tim, the Duct Tape Guys."

"We say there are two rules to get you through life: If it's stuck and it's not supposed to be, use WD-40. If it's not stuck and it's supposed to be, you duct tape it. They're the yin and yang of your toolbox."

Nyberg and Jim Berg, who are brothers-in-law, have been finding humor in duct tape for nine years, writing five books on the subject (plus another on WD-40) and doing stand-up duct tape jokes on television and at home shows. (Sample: "Turn any floor or table lamp into a ceiling fixture. Just duct tape it upside-down to the ceiling.")

They're not the only ones who find duct tape inherently funny.

The new movie Red Green's Duct Tape Forever is based on the Canadian comedy television series, Red Green, which stars a handyman in a fishing lodge who uses duct tape ("the handyman's secret weapon") to make bizarre projects such as taping home heating ducts together to make a pontoon boat.

Garrison Keillor invented a fictional sponsor called the American Duct Tape Council on his radio show, A Prairie Home Companion. And Tom and Ray Magliozzi, hosts of Car Talk on National Public Radio, have been known to play the song "Duct Tape Madrigal in C Major" on the show, an audience favorite.

Then there's Scott, the duct tape artist, from Winnipeg Beach, Manitoba. Scott, 30, has sculpted such works of duct tape art as a bear skin rug, the Empire State building, and a bison, the symbol of Manitoba. He considers his work "modern folk art." Duct tape, he says, "is funny because of the things you can do with it. I was sitting down the other day making a space shuttle and it just made me laugh. It really looks like the space shuttle."

Duct tape "is wicked funny," agrees Dave Lavalle of Chelmsford, Mass., founder of the Mr. Handyman franchise, a home handyman service.

"When you use duct tape, you are considered a hacker, someone who's not doing the job the right way. It's a patch. It's a temporary situation that typically ends up being a long-term solution."