Over the past five years, I've up-loaded more than 200 pictures to Facebook. Some are of me. Some are of my friends. Most are of me and my friends doing mildly embarrassing things. But none has elicited as much enthusiasm as the snapshot I took recently at a Brooklyn flea market. The response has little to do, I think, with what actually appears in the image: an assortment of old Owl-brand stamps, seen from above. Nor can I credit the other tchotchkes edging into the picture: a beaded necklace, a crystal bowl, a leather sleeve of sorts, a silver object that may or may not be a harmonica. What makes this particular digital photo popular on Facebook is the fact that it doesn't look digital at all. After extracting the original file from my Nikon, I dragged it into a program called Poladroid, which quickly spit out an image that belied my DSLR's multi-megapixel specifications: jaundiced tint, fuzzy focus, textured white border. And yet, the moment I posted the photo online, admirers rushed to ask how I "vintagefied" it. The consensus, as one tech-savvy correspondent put it: "This looks so great."

If you were to pick the demographic group most likely to champion the antiquated Polaroid picture, the young and wired—or, to be more exact, those too young and too wired to have ever used a Polaroid camera themselves—would not be it. But analog obsolescence has a way of making the postmillennial heart grow fonder, and with physical Polaroids bound for extinction, the Polaroid esthetic has in recent months become a rather ubiquitous signifier of cool. In February 2008, the Polaroid company, which had stopped selling instant cameras a year earlier, announced that it would cease producing its instant film as well, and by the beginning of 2009, all five of its remaining plants had been shuttered. Whatever film was left in stores was it. Polaroid enthusiasts flipped, scouring shops for leftover stock and propelling the price of a Polaroid packet into the high double digits. Some turned to activism (SavePolaroid.com); others began to archive prints online (Polanoid.net). A group called the Impossible Project even leased an abandoned Polaroid factory in the Netherlands and recruited a team of former Polaroid technicians to invent a new instant film. Soon the art world's longstanding passion for Polaroids began to trickle down to people who'd never shown a particular interest in the format—like, say, my Facebook friends, who can now consume their entire diet of hipster imagery in Polaroid form, from Porter Hovey's hazy blog to Matt Schwartz's sunburned prints; from the Polaroid-only photostream by indie rockers the Kills to 12 Instances, a recent show at New York's Heist Gallery. On a single afternoon in early June, I stumbled upon two more Polaroid tie-ins: an iPhone app called ShakeIt that "develops" its virtual Polaroids faster when the device is joggled, and the Polaroid Party, an N.Y.C. fete where guests pinned their own pics alongside prehung prints by local artistes. You'd almost think Polaroid is the new black.

But why, and why now? As faddish as it may seem, I suspect that the eleventh-hour Polaroid resurrection actually reflects a latent uneasiness with the changing role of photography in our culture—and a deeper discomfort with how that shift is affecting the way we remember. Of course, nostalgia is nothing new; Edward Steichen probably lamented the loss of the daguerreotype. But unlike earlier periods of progress, the Information Age isn't replacing old objects with new ones. It's using 1's and 0's to get rid of objects altogether. As larger swaths of our lives become immaterial, we tend to rely on computers to preserve or reproduce (or simply promote) the esthetics of the more tangible technologies they're displacing. Hence sites like Muxtape (which replicates the mix-tape experience in MP3 form) and Telegram Stop (which mails electronic missives in typewritten 19th-century packages). The Polaroid revival is a symptom of the same condition. When all of our infinitely replicable, infinitely Photoshoppable images reside on hidden hard drives, the idea of a whirring box that instantly gen-erates a single unreproducible print has a certain comforting allure. It's still remarkable, even magical. But it's one step less removed from reality.

To be sure, that description could apply to any kind of photographic print, instantaneous or not. What makes the Polaroid picture special—and suddenly so resonant—is the way its formal qualities dovetail with the mechanics of memory. If cameras are "clocks for seeing," as the critic Roland Barthes once wrote, the Polaroid is a particularly potent timepiece. For much of its history, photography marked the moments sporadically (each roll of film contained a limited number of images) or abstractly (in black and white); we were required to exercise our mnemonic muscles by supplying the color or recalling the context. But digital photography rewrote the rules, parceling out the past in a flood of images that are as detailed and consecutive as our devices allow. The misty mental process of recollection and imagination that once filled the gaps in and around our pictures is no longer strictly necessary; we can simply point, click, and consult Flickr later, without ever taxing our gray matter. The Polaroid serves as a palpable re-minder of the pleasures of good old-fashioned remembering. For one thing, it materializes in real time, making it the only form of photography that transcends mere documentation to become part of the moment it's meant to preserve; we blow out the candles, look at the Polaroid, and archive both experiences as one. And while digital images strive for inhuman fidelity—the more megapixels, the better—Polaroids in-advertently warp, and thus estheticize, every moment they capture, cropping a panoramic world into a soft, summery square, then mounting the image inside its own albescent frame. People often describe the effect as "nostalgic"; what they mean, I think, is that Polaroids look like memories—imperfect and incomplete, but somehow realer for it. In an era that encourages us to forget how to remember, that's a seductive anachronism.

Don't get me wrong. Brooklyn's Polaroid Party goers aren't contemplating the metaphysics of memory as they snap photos in some massive exposed-brick loft space. They just like the way Polaroids look. Most of them, in fact, aren't even using Polaroid cameras; for the young and wired, programs like Poladroid are far more practical. But maybe that's a good thing. As the remaining supply of Polaroid film dwindles and millions of SX-70s are finally rendered useless, it's nice to know that we'll still have some small, visible reminder of how the past was preserved before memory was obsolete—even if we'll have to log on to Facebook to remember.