The tale of the Web site Tired.com shows just what the Internet once was, and what it has become.

In 1997, a San Francisco Web designer named Mike Kuniavsky bought the Web address on a lark. He wasn't sure what to do with it but posted a brief message on the Web site as a placeholder: "Are you tired? Tell us why." Clicking on "us" sent visitors, mysteriously, to a blank email form addressed to tired@tired.com -- an address that Mr. Kuniavsky set up to forward to his personal email inbox. The submissions were never to be published online.

The first message came within hours. Dozens more arrived within weeks. Nine years later, there's a pile of emails in Mr. Kuniavsky's inbox more than 42,000 deep -- from overworked kids, overwhelmed parents and other fatigued Web surfers (more or less in that order, he says).

The simplest kind of tiredness, of course, is from lack of sleep: "Because I've been awake too long writing a sermon," one person recently wrote, briefly, to Mr. Kuniavsky. But there are other, more complicated woes that manifest in tiredness, Mr. Kuniavsky has found. Job dissatisfaction is common among adults. ("I'm tired of bad customers at my restaurant," one person writes.) For kids, it's the pressure of school, homework and afterschool activities.

Tales of romantic frustration also are common, predictably. One note reads: "I'm tired of dealing with two women at once, and then breaking it off with one only to have the other break it off with me."

Today, people use the Internet to share with strangers some bits of their lives -- offering amateur reviews of favorite books and restaurants, sharing photos and describing themselves in great detail on dating sites. Sites like PostSecret.com and NotProud.com invite visitors to spill their secrets on public message boards.

But that hasn't always been the case. Early on, the only way to publish anything online was to send an email to a group of friends or post a note in an online newsgroup. We surfed the Web passively. If we wrote to a message board, it was to discuss a specific topic.

Mr. Kuniavsky's site, then, was rare in its day. It asked people to write things online to the private email of a perfect stranger that they would never write for public consumption. That struck a chord. By 2000, he was receiving a few dozen emails a day.

Mr. Kuniavsky, now 38 years old, happens to be a social scientist who specializes in researching how people use the Internet. A few years after starting Tired.com, he co-founded a Web-design firm called Adaptive Path. This year, he co-founded a product-design studio called ThingM. He has a theory about why his site inspires frankness. "Tiredness is the product of the weight of your life on your shoulders," he says. "And when people are articulating why they're tired, it's a window into the difficult-yet-mundane details of their lives."

He has left the site looking exactly as it did nine years ago: the six words written in small, typewriter-like font against a stark-white background. It feels quaint and old-fashioned. When the question was first posed, our collective guard wasn't up the way it is today. Now, who would send an email to an anonymous recipient without worrying about ending up the victim of some email scam or finding the message mockingly splashed all over the Web? Indeed, Mr. Kuniavsky has been receiving fewer emails lately -- about eight a day, he says, one-third the number he received in 2000.

But those that do arrive shed light on the Internet's nature as a virtual confessional -- especially for those not old enough to remember when the Web worked differently.

"I'm 11 and I go to school in Manhattan, even though I live in Brooklyn. That means I have to wake up at six," writes one self-diagnosed insomniac, adding that his or her mother "doesn't think I'm old enough for sleeping pills."

Another starts, "I get up early for school or jazz, then go to bed late because of homework or marching or procrastinating." The writer describes a laundry list of chores and afterschool activities -- and then adds, as if it were an afterthought, "I'm sick of taking so many medicines for cystic fibrosis."

Then there are the grown-ups. One email reads, "I'm a lecturer and these damn students have worn me out." Another, with the subject line, "of gilbert," starts, "i am tired of my husband gilbert he accuses me of cheating no matter what i do ..."

For a while, Mr. Kuniavsky received a daily email from someone who seemed to be a homeless man writing from a San Jose, Calif., library. Others write incendiary messages from investment banks, accounting firms and law offices -- followed by frantic notes retracting it all.

Last year, Mr. Kuniavsky posted a list on his blog of the top 250 most-written words in the messages he received in 2004. Among them: "work" (No. 39), "school" (77), "house" (190), "money" (191), "family" (217), "sick" (226), and "kids" (250). The most-used word, as you might expect, is "tired." The second, tellingly, is "I."