While some have expressed disapproval, including the Australian police and prime minister, the spotlight has helped the activity reach a wider audience.
All the recent attention has sparked a flood of fresh planking photos, as well as YouTube clips of television-news anchors face down on their desks.
Diplo, a popular electronic-music DJ, wrote on Twitter: "planking right now." A spokesperson for Honey Bunches of Oats (yes, the cereal) promoted safe planking in a message on its blog Monday.
"It's the most fun you can have being still," Sam Smith, from Australia, wrote on Facebook.
You could waste hours clicking through the photos posted on the Planking page on Facebook, which has more than 180,000 members. There are plenty more to be found in the planking tag pages on Tumblr and Flickr, and they're also showing up on CNN iReport.
Among the gems: a woman lying on a bar, a man planking across the humps of two live camels' backs, a group face-down on an escalator, a woman on Kmart shopping carts, and a guy prone across the shelves of a convenience-store refrigerator.
The concept has been around for at least a decade, according to an English duo which takes credit for its invention and was profiled in a 2009 column in the Toronto Star. Then, it was called the Lying Down Game. (Not exactly a catchy name.)
The pair created a Facebook group and a website -- which smartly has a disclaimer: "The originators of the Lying Down Game cannot be held liable for any accidents, injuries or criminal proceedings." Tens of thousands subscribe to public pages celebrating the game.
The subject came to light in September 2009 when seven medical professionals in England were suspended for playing the Lying Down Game on the job. A superior had spotted the pictures after they had been posted to Facebook.
Plankers say the activity is generally harmless fun -- though that idea was challenged last week. Some even refer to it, tongue-in-cheek, as a type of alternative sport.
"Planking is an extreme sport which requires years of constant training to perfect the complex technique," wrote Jake Mason on the Planking Facebook page.
The game hasn't won over everyone, and those opposed are especially vocal. A bunch of anti-planking pages have sprung up on Facebook.
"Is it really that hard to find something to do with our time?" Shannon Lynch, an art student in California, posted on her Facebook page. "Maybe we should start a craze about picking up litter."
Others are just offended that the media circus has plucked their hobby from obscurity. Steve Molk, a radio personality in Brisbane, Australia, declares that planking has "jumped the shark."
Hopefully that won't give anyone ideas about planking an actual shark.
