Like tens of thousands of other commuters, Alex Klimento gets up long before dawn to begin the trek to the city. On a good morning, when the traffic is merely congested and not completely gridlocked, he gets to Fisherman's Wharf after about 75 minutes.

Once there, the Russian immigrant keeps right on driving. Past Fisherman's Wharf to the Marina. Over to the Financial District. Across to the North Beach shopping district. And back to Fisherman's Wharf. Then he does it again. And again. All day long, until 4 p.m., when he starts the rush-hour journey back to Vallejo on the other side of the bay.

Klimento drives a truck, but never makes any deliveries. Or rather, he's continuously delivering something--information. The panels of his 28-foot-long, 12-foot-high Mitsubishi Fuso are a mobile billboard for GiftCertificates.com. It's a virtual truck for a virtual company.

"In Russia," Klimento said in his uncertain English, "no one would do this. They have not enough money. It is an economical problem."

In America, the economical problem is the opposite. Internet companies have so much money to spend on advertising that there isn't enough advertising space to go around.

It's a problem in many places in the country, but worst here. Television? Sold out. Radio? Unavailable except at ridiculously inflated "bump" rates. Billboards along Highway 101 in the heart of Silicon Valley? Not a chance.

Yet the companies must spend, because otherwise they have no hope of gaining any customers and thus remaining alive until Christmas 2000. So they're increasingly turning to unconventional advertising. Like the Internet itself, Internet ads are making inroads everywhere--often in places that used to be relatively ad-free.

ArtistOne.com, an online community site, is touting itself on a giant barge in San Francisco Bay. CNet, a news site, is advertising on airport jetways--space the airlines used to reserve for themselves. Yahoo, not content with merely advertising on the top of taxis, is transforming the cabs into unmissable purple Yahoomobiles. Santa.com organized the world's first dot.com parade.

Nothing is sacred, almost. A Texas start-up, CarOrder.com, offered to pay $400,000 to hang its banner for one day from the toll plaza of the Golden Gate Bridge, as well as forking over another $160,000 to pay everyone's tolls for that day. At first the bridge district was inclined to do the deal, but the proposal has bogged down in controversy.

A Northern California aerial advertising record was set at last month's football game between rivals Cal and Stanford at Stanford Stadium: Eight planes displayed 37 banners, half touting dot.com companies. Meanwhile, companies such as Hotjobs.com have regular flights over the city, while Monster.com has been renting a blimp and 3Com hired a skywriter to extol the virtues of its palm-sized hand-held computer over San Jose.

Companies are waking up to the advantages of advertising in the heavens, said Joel Jaye, chief operations officer of a San Leandro company that used to be known as Aerial Media but is changing its name to Airads.com. "Regardless of what your spirituality is, everyone imagines being up there at the end, and so people trust what's in the sky a whole lot more," Jaye said.

Soon there will be much more to trust. "The sky will become much more of a canvas, thanks to the dot.coms," promised Jaye. "I'm taking three to five new calls a day."

Food.com found its niche in a more high-tech sphere: the instant in which a customer has finished an ATM transaction but has not yet received the card back and the cash. For that brief moment, the Food.com logo flashes on the screen.

"It's different, it's new, and it alerted people to my brand in an environment where they're not used to seeing any advertising," said Food.com vice president of marketing Angela Wilson Gyetvan.

After a test with 600 automated teller machines in Seattle, San Francisco and Boston in October, Food.com's business climbed 35 percent. That inspired the takeout and delivery service to expand to 1,110 ATMs in a dozen cities, including Washington. A bonus is that it's cheap. "Less than 10 newspaper ads," is all Gyetvan would say, which means less than $200,000 a month.

On the other hand, unlike a newspaper ad, the ATM spot doesn't give much time to linger over or even read the copy. It's a question much on these marketers' minds: When does an innovatively located ad become ineffective, silly or even irritating?

C I Host, a Web hosting solutions provider, proudly announced last month that it bought space on the back of Evander Holyfield's trunks for his heavyweight bout against Lennox Lewis. "Winners identify with winners," company chief executive Christopher Faulker explained at the time. Too bad Holyfield lost.

Send.com, a luxury gifts site, did an aerial ad at the Ryder Cup in Boston in September. "I sat there and watched our plane circle overhead with five other planes," chief executive officer Michael Lannon said. "I looked at the audience, and no one was looking up. That's not the way I want to introduce myself."

Although Send.com is spending $20 million on holiday advertising, it's keeping as much as possible to the traditional print, radio and television ads.

"You never see Tiffany's on the corner handing out fliers. Just because someone will print your name on bumper stickers doesn't mean you should do it," Lannon said. "We're trying to build a brand, create a relationship. We want to become friends with you, not stalk you outside your house and bang on your window."

Jonas Lee, the chief executive of GiftCertificates.com, is more hopeful about people adapting to these new forms of advertising. "I remember being in New York City when they first started doing ads before movies, and people would boo," Lee said. "Then they made them more entertaining, and people now look at them as part of the landscape. And on the Internet, everyone hated banner advertising at first, and then they realized they could live with it."

GiftCertificates.com is a typical start-up company: It has $24.5 million in funding, of which it's spending half on marketing this holiday season; it has the obligatory celebrity spokesperson (Sophia Loren); it has a bunch of similarly named competitors that also sell consumers gift certificates for online and offline merchants (Giftpoint.com, GiftSpot.com).

Lee started using the billboard trucks because he couldn't get any other advertising here at prices that were even slightly reasonable. The Highway 101 billboards, for example, cost $10,000 to $30,000 a month last Christmas, depending on size and location. Now they're double that, if you can get one at all.

But Lee had to get his company's name out there, lest he lose ground to those competitors. He also liked the physical nature of the trucks. "If you're a bricks-and-mortar store, you have a sign on the door. In effect, you have your own billboard," he said. "But if a dot.com doesn't advertise, no one sees them. You become less real."

At the moment, GiftCertificates.com has 14 trucks in five cities, including Washington. Each truck costs $15,000 to $30,000 per month. So far, Lee is satisfied, but noted: "There's a lot of trust involved here. How do you know it's out there on the streets, and not in a garage somewhere?"

The three trucks he has in San Francisco, including Alex Klimento's, belong to Montage Moving Sound and Billboards, a New York company. Owner Elan Nissim said he got in the advertising game through his fashion business.

His trucks were delivering clothes while advertising the garment company on the side panels. Nissim figured it was simpler to stop making real-world deliveries. He now has 200 mobile billboards on trucks designed to carry little else, with the Internet companies a rapidly growing share of the business.

In the District, GiftCertificates.com is using Do It Outdoors, a York, Pa., company. Regis Maher, the owner, has 24 trucks, with six on order. "If I had another 100 trucks, I could fill them," Maher said.

"The uniqueness of the whole thing is why it's working," he added. "Because it's such a different medium, the first time you see it, you remember what was on there."

Yet the trucks are also contributing, however symbolically, to the congestion that everyone hates. "As a driver rather than an Internet observer, I find the moving billboards extremely annoying, especially if there's gridlock," said Bradley Johnson, interactive editor of Advertising Age. "I try to remember the companies they advertise so I can make sure not to order from them."

"With a million cars out there, is one more going to make a difference?" Maher protested, evoking the two traditional defenses of advertisers: "It's a freedom of speech issue. And [the trucks are] almost a form of entertainment." Most mobile billboards are equipped with speakers, to add another way to get noticed. The owners said these are used sparingly, at least for the moment.

Alex Klimento doesn't concern himself with such arguments. Now 50, he came to this country seven years ago from Russia, where he was a doctor. "I never dreamed I would be doing this, but the reality of life in America forces me to do it."

His real home is in New York; here he is camping in a Days Inn in suburban Vallejo. His son, also named Alex, is a driver here as well, and when they pass in the streets they wave. The elder Alex gets no exercise, but tries to eat healthily. For a morning snack he has brought along some Evian and an orange. At night he reads (at the moment a book by former New York mayor Ed Koch) or watches the History Channel.

Spending the whole day, seven days a week, alternating between stop-and-go freeway traffic and crowded urban streets would fit many commuters' definition of hell.

"Do I like to drive?" Klimento pondered the question. "I like to get paid for my work. And this is work. I must pay attention. I'm driving a vehicle, a transport device. I can make an accident if not paying strict attention."

He drives slowly, although not as leisurely as he did before getting a $100 ticket a few weeks ago when he was merely inching along. He's in no hurry to get anywhere, because he's already there. The worst traffic doesn't ruffle him. "The more traffic, the better it is for the truck, no?" he asked.