Each October, as it begins to get dark earlier and earlier, I find myself instinctively dreading the end of day. It's a feeling left over from my teenage years, when sundown used to signal winding down and a realization that what had started with so much promise at sunrise was doomed to another quiet, boring finish. I remember school nights in the early '90s filled with nothing to do (after I finished homework, of course). My family owned just one VHS tape ("Arachnophobia"), my parents treated the TV as a device that entered sleep mode at 11 p.m. and my long battles of "no, you say goodbye first" with some high school boyfriend got old fast. But these days, instant messaging, TiVo and my cell phone make the very notion of dismay over "day's end" seem as old-fashioned as getting worked up over sliced bread.

Sure, the light bulb hedged daylight more than a century ago, but today's technological advancements have obliterated the usual constraints of time and even space. As a result, 24/7 has gone from extreme to routine, and the idea of an end to the day has been replaced by an "it's business hours somewhere" mentality. A Verizon commercial I heard on the radio recently says it all: Thanks to your cell phone, "You can put Father Time in a headlock and give him a great big noogie."

In case you hadn't noticed, the dead of night is suddenly alive. It's not just clubgoers, security guards and bakers who make the most of the graveyard shift; it's easier than ever to be an insomniac (or at least to intersect with one). CEOs e-mail their subordinates after midnight, my brother monitors his eBay account all night long and my mother-in-law keeps Fox cable news on to help her sleep. (Who knew that early morning stumbles to the bathroom could also be prime time for the latest on the Laci Peterson case?) In effect, technology has helped fashion a parallel universe, populated by night owls who find comfort in the glow of pixelated screens. Who can go to bed when your doppelganger is looking to make a connection? Who wants to risk missing something or matching up with someone?

All it takes is a little time alone, especially late at night, to confirm how much technology has transformed culture and how it has changed the way we relate to each other. That's because being alone is not what it used to be. These days, even momentary solitude seems like something to be avoided at all cost. And technology makes it possible: Thanks to cell phones, no one has to face that stroll down the street, the five-minute commute or the lunch line without companionship. With hands-free speed-dial, the solitude of a Stairmaster -- apparently a frightening prospect for some fitness fanatics -- is a thing of the past. (Don't scoff. I've seen it.)

Even insomniacs find camaraderie in this dual universe. "Anyone out there?" is how many denizens of eBay's Night Owl's Nest (a forum for "night crawlers and insomniacs of eBay to meet and greet other creatures of the night") often open an online conversation. On a recent night, "zombie*grrl," up late watching the National Geographic channel and popping Ambien (to help her fall asleep), wrote in to share a story about a trip to the bathroom where she, in her daze, winds up falling into the bathtub. Instead of waiting until the next day to share her embarrassment, she signs on and gets immediate recognition. Other patrons respond with an LOL (Laughing Out Loud, for those still clueless about the New Techno-English) and she, like so many others, finds a bit of solace in this "warm corner of the cyberspace world."

But the highly coveted "anywhere, anytime" access (is there a telecom company anywhere, anytime that doesn't use that line?) really means being available everywhere, all-the-time -- but more and more, it means late and later. At least that's what technology promotes: Cell phones are cheapest after 9 p.m., some video stores stay open all night and, at any given hour, there's a virtual world of people you could be connecting with in cyberspace. There's no day's end when a.m. can just as easily be p.m. -- and often is both, if you're chatting with someone overseas. And exactly what time is bedtime when cable and network TV offer news and entertainment (whatever the quality) in every time slot, all night long?

For the younger generation growing up today, "whenever, wherever" has become a way of life. Multitasking is so mainstream. Teens communicate when and where they choose -- they're firing off text messages on the fly, in the classroom or late at night when they're supposed to be sleeping. They're so wired that they make twenty-somethings like me nervous. A friend in New York recently lamented, "It's weird, there are teeny-boppers with BlackBerrys running all over the subways," he said, as if he had seen a newborn consuming Starbucks coffee instead of milk.

A recent visit from my 11-year-old niece was similarly upsetting for me. Haley arrived in San Francisco, wielding mobile phone and blue iPod mini, and fresh from watching a DVD in the SUV on the way up. When I hear "road trip," I think "Are we there yet?" and remember endless games of "20 Questions," dodging airborne drool from my dog Gus and seatbelt-constricted wrestling with my twin sister. Haley's last road trip was over before she could finish "Finding Nemo" or ask (even once) "How much longer?"

To board an airplane, Haley still needs adult accompaniment to the gate and a notarized letter from her parents. But she can break through plenty of other barriers by herself. She can send text messages from San Francisco to her home in New York, she carries her own 1,000-song soundtrack with her wherever she goes, and between the DVD library at home (more than 500 movies) and IM-ing friends, nighttime entertainment (parents permitting) is rich with possibilities.

I wonder how all this new techie bling will transform Haley, and how things will be different when she's my age. When I was 11, a sacred staple of classroom behavior was passing notes. Based on observing Haley's day-and-night interconnectedness, the very idea of using paper to communicate might cause Haley to "FOCL" (Falling Off Chair Laughing).

At any given time, late at night, far or near, messages filled with such eloquence as "RUOK," "CUL8R," and "DEGT" (Don't Even Go There), are zapped back and forth and then lost forever. "Doesn't she want to save that?" I thought. Feeling like the nostalgia police, I wanted to show her what I've saved from my youth: boxes (and boxes) of everything written to me -- notes passed in the second grade, love letters from boyfriends I'd scarcely remember otherwise, graduation cards. If messages are created only to be purged, what would Haley do when she needs to produce irrefutable documentation of who broke up with whom in the sixth grade?

In this age of broken boundaries and unbroken days, nearly every interaction is informed by some sort of technological device. I found my last job on Craigslist, where I met a woman who found her husband-to-be on Match.com. A high-school friend recently e-mailed to say she met someone on Friendster who knows me from college.

So it seems as if it should be easier for everyone to connect, late at night or whenever. But the more technology we turn on, the more relationships we have to manage simultaneously -- and the more likely we are to ask our best friends if they can hold. I have programmable phone lists and speed dial at my fingertips, and yet I feel more disconnected than ever -- somehow, it's easier than ever to be two places at once but nearly impossible to, as my mom says, just "be here now." Yet being in two places at once has become strangely familiar: You don't just go out to lunch with a friend anymore. You go out to lunch with the friend and the friend's cell phone book. Everyone has gotten used to having another self to answer for (though only some people have Madonna for their ring tone).

So, of course, there's even technology to help you avoid people: Phone companies like Nokia, Sony Ericsson, Virgin Mobile and Cingular now offer software to help you exit a situation or create a false alibi. Cingular's "Escape-a-Date" offers fake "rescue" calls -- a prearranged service that walks you through what to say before suddenly dropping a date gone sour. And Soundercover adds a recorded background to "help you sound where you're supposed to be."

It's not that I disdain the benefits of the parallel universe. I exchange e-mails and voice mail with friends, and I'm glad to have been able to meet new puppies, kittens and babies in my inbox that I've never met in the flesh.

At the same time, it's almost impossible to avoid the draw of the linked-up lifestyle. Many employees feel the need to be "reachable at all times." And more and more companies require it. In the era of the borderless office, the workday never really ends. Sarah Foelske, an art director in New York, says she feels "like I have to be constantly connected" and often leaves work after 10 p.m. "only to go home and turn on the Internet." As a result she says, "E-mail and being online makes you feel lonelier in a way, trying to be connected all the time."

It's so common now to correspond by e-mail alone, it's easy to go for days without actually interacting with a real live human. As a twin, accustomed to sharing everything from birth to the same high-pitched laugh with my sister, I used to hate being alone. I remember asking my Mom if she got sad when my Dad left on business trips. "I do miss him," she would say. "But I really like having alone time, it's nice to be by yourself." I think I turned around before I mouthed, "What a loser."

If I used to dread day's end, now I dread the endless day. The more connected I am, the more I wish I could turn back the clock (and not just one hour). Now that I can get a call anytime, anywhere, I find myself screening my calls whenever, wherever. Who wants to waste even a few minutes on the phone to chat with someone who's only filling time while going from one place to another? These days, I have no problem saying goodbye first. And staying up late so I can get my real twin on the cell phone is no substitute for having her in a real headlock and hearing her LOL when I give her a great big noogie.

Author's e-mail:

getchesc@yahoo.com

Catie Getches is a freelance writer in California who can be reached sometimes, somewhere in the Pacific time zone.

In today's 24-hour world, you don't just get together for a night with friends anymore. You get together with their cell phones, too.