Look what Alex Tew did, and you get one of those “Why didn’t I think of that?” flashes. It’s so simple, so cheap, so mind-bogglingly lucrative that it took the 21-year-old student from small-town Wiltshire, England, not even five months to go from broke to millionaire.

Worried about paying his college tuition last August, Mr. Tew chanced upon one of those rare original moneymaking ideas. How about creating an Internet Web page out of 1 million blank pixels? And then selling those pinhead size digital picture elements that make up a computer screen for a dollar apiece, or $100 per 10-by-10-pixel block, to advertisers who turn them into colorful tiny billboards and micro logos linked to their own Web sites?

And why not call this new marketing monstrosity “The Million Dollar Homepage” – since he stood to make a million bucks?

At exactly 1:42:28 p.m. yesterday, Mr. Tew could post a “sold out” sign on his buzz-generating Web site, the Million Dollar Homepage. (You can see it at www.milliondollarhomepage.com.) The spiky-haired Brit put the last thousand pixels up for auction on eBay 10 days ago with a $1 starting bid for the lot. With 24 hours to go, Tuesday’s bidding reached $152,300, putting him over the million-dollar mark.

“I’m half-expecting a last-minute flurry of bids. I think it is going to go higher,” says Mr. Tew, whose initial investment to set up the pixel page was less than $100. “I never imagined things would get to the level that they have.”

Unsure initially that a single pixel would sell, Mr. Tew felt the idea had potential, so he aimed high. “I asked myself the question, ‘How could I become a millionaire?’ Twenty minutes later I had the answer,” he says. In the beginning, he reasoned, even 1% or 2% of a million dollars wouldn’t be bad.

The phenomenon he created has been hailed by some as a genre-changing concept in online marketing – otherwise an advertising badlands of spam, banner ads, and pop-ups. Others say it’s a brilliant, one-time marketing aberration that will never be replicated.

Whatever it is, the Million Dollar Homepage isn’t a pretty site – even as it nears completion and begins a guaranteed minimum five-year lifespan. Mr. Tew calls this head-cocking creation “a big collage of different colored ads.” It looks like a bulletin board on designer steroids, an advertising train wreck you can’t not look at. Think “Where’s Waldo?,” only more cluttered and without a Waldo. It’s like getting every pop-up ad you ever got in your life, at once. It’s the Internet equivalent of suddenly feeling like you want to take a shower.

But its conceptual beauty is that it’s not designed at all. How the pieces fit together is totally random. Buyers create little ads and choose open ad space on a 10,000-block grid. It’s more than 2,000 advertisements, their dimensions ranging from postage-stamp size to a Tart N’ Tiny candy (sorry, we couldn’t think of anything else small enough to compare!), displaying words normally red-flagged by spam filters – EZ Money! Hair loss? Poker! Loans! Get Girls! Freebies! Cancer Cure! Casino!

Some of the ads are illustrations or photos – images of bikini babes, cartoons, Che Guevara, the British flag, a marijuana leaf, a bull’s-eye, the dollar sign. When you drag the cursor over any one of them, a small read-out appears identifying the advertiser – dating services, online poker, loan companies, bookies, bloggers, ring tone sellers, snoring remedies.

Within the first month the site was getting 200,000 unique visitors daily, and more than 3.2 million in the past two weeks, Mr. Tew says. “The more people talked about the site, the more money I made,” says Mr. Tew. “And the more money I made, the more people talked about the site. It’s a self-perpetuating idea.”

The idea has inspired a bad case of pixel envy online. More than 1,000 copycat homepages have cropped up hoping to duplicate his success – from the Zero Dollar Homepage, which gives pixel blocks away and tries to make money from banner ads, to “The Most Expensive Pixels on the Internet” that sells space for $1,000 per pixel.

Twists and oddities also abound: The Million Pixel Gallery tries to sell art and advertising from galleries and museums, the Cover Up Osama Bin Laden site sells pixel blocks to obliterate Osama’s face from the screen, and the Million Booby Homepage, well, appears to still be in the training-bra stage of development.

Few if any of the me-Tew’ers are likely to make a million dollars or even come close. Many remain barren sites without a single ad. One of the first was the Million Dollar Web Page created by Anthony Van Noordwyk, an Omaha Internet techie who launched a couple weeks after marveling at Mr. Tew’s homepage. But while his unique visitors’ count is up from four the first day to 2,115 Monday, he has sold just 60 ads.

“Nobody is anywhere close to being as successful as Alex’s original,” says Mr. Van Noordwyk, 35, who counts his sales so far in the tens of thousands. “Now that Alex’s Web page is full, maybe some of the more popular pixel ad sites will catch on a bit. I am not holding my breath but I am crossing my fingers.”

While a few pixel pages are dedicated to the Internet’s biggest moneymaking venture, most copycat pages draw the line on pornography. “We had to them away because other advertisers wouldn’t advertise,” says Josh Moser, co-creator of the Million Quarter Webpage, which sells pixel blocks for 25 cents per pixel.

“This is probably going to be a fad,” says Mr. Moser, 31, a Detroit Web site developer whose site went live a month after Mr. Tew’s and now has 400 advertisers.

Including sales on their new site, PixelGiveaway.com, he and partner Jeremy Mlynarek, 29, have sold more than $85,000 in ads, Mr. Moser says.

Gareth “Gaz” Thomas, 24, a biotechnology doctorate student from North Wales, Britain, uses sex appeal to sell one-penny pixels on his SexyPixelHomepage.com site where ads gradually are blocking out a side view of a naked female torso.

“How could an idea that was so unique and different spawn so many dull copycats?” says Mr. Thomas, who three months ago didn’t know the first thing about creating a Web site, but has sold nearly 100 ads. “I made mine sexy so it would grab attention and it works!”

While Mr. Tew thinks the copycats are “quite funny, really,” he doesn’t like the “rip-off sites” that borrow heavily from his. “I like the ones that put a twist on it and improve the idea,” he says, mentioning a favorite, TrumpingAlex.com, which features a photo of Tew with a Donald Trump hairstyle superimposed on his head. “But the one thing that everybody seems to be missing is that it’s one of those crazy ideas that only works once. I was first to market and therefore I got 99 percent of the attention. Good luck to the imitators.”

If his pixel page has any lasting value in online marketing, Mr. Tew believes it’s that “very small ads have some sort of future.”

And his future? He’s putting his business management studies on hold. He’s had job offers, business opportunities, and a few new ideas he wants to explore. Not to mention a million dollars.

“The lesson is that consumers are willing to go to good ideas, things that are unique, things that are novel,” says Mr. Tew. “Rather than copy each other, spend time thinking up new things. … Creativity works.”