The Internet, famously and ad nauseam, is all about choice. It has something for everyone: carnivores and vegetarians, city slickers and country folk, people who like advertising and people who don't.

Yes, there are people who like advertising, or at least people who don't dislike it. Jim Jorgensen is banking on it. Barry Jaspan, meanwhile, is after the rest of the crowd.

Jorgensen is chief executive officer ofAllAdvantage.com, a Silicon Valley start-up that pays people to watch ads. For each hour they're online, they earn 50 cents, up to $20 per month. AllAdvantage . com will send users checks by mail.

Customers download a small program that launches whenever they're online. It inserts a long, narrow window across the bottom of the computer screen that features an advertisement. The software also keeps track of the time they spend surfing the Web, sending the information back to AllAdvantage . com every 20 seconds.

It does not sound like a feature for which there is a crying need. Yet Jorgensen says 25,000 people signed up for the service on Tuesday, the first day it was available, and he expects the number of users to reach six figures by next week.

"This is a member-service company," Jorgensen says. Of course, AllAdvantage . com will use information about its customers' habits to sell advertising. But he says it will not reveal information about individual users.

In fact, he sees the company as a kind of capitalist collective; it will spend little if any money on advertising, instead relying on members (and, it must be said, newspaper articles) to spread the word. It even has sample e-mail messages available for downloading at the site.

"We plan to deliver the majority of our revenues to our customers," he says. If all goes well, the rate per hour may increase to $1 or more.

And what if people don't like it? The ad "can be closed with one click," he says. "Any time you don't want it there, just get rid of it." It differs from software from such companies as NetZero, which offers free Internet access but inserts a roving ad on a computer screen that is impossible to exterminate.

"Our whole philosophy is based on individual choice," Jorgensen says.

Which sounds a lot like what Barry Jaspan says. Jaspan is president of Internet Mute, a Boston firm that makes software to block advertising on the Internet.

"I think of it as an annoyance blocker," he says. The software also helps Web pages load more quickly, since many ads are graphics- intensive.

Intermute, his company's sole product, uses a variety of tactics - such as searching for elements that measure 468 by 60 pixels, the standard dimension of banner ads, or any information delivered from Doubleclick.net, a kind of Web ad agency - to identify ads and then prevent them from appearing onscreen.

But isn't advertising paying for all the wondrous stuff people log on to see? And couldn't Intermute - and similar software, such as WebWasher or AtGuard - kill the goose that laid the golden egg?

Not really, Jaspan says. "I really don't think this is going to kill off Internet advertising," he says. Advertising is already well- entrenched on the Web, and, besides, there are people who actually enjoy it.

"Some people like seeing ads," he says. "It's a big world out there."

So it is. And it may be that it's big enough for both of them. Or it may be that size is not the issue.

Jim Nail, an analyst for Forrester Research, notes that the problem is not necessarily advertising on the Internet. It is the right kind of advertising. Thus, attempts to filter Internet ads may be just as misguided as plans to augment them.

"People already have an extremely efficient filter against banner ads," he says. "Their brains."

As for an additional bar across the bottom of a computer screen, Nail notes that what Internet advertisers covet is interaction with their audience, not merely its attention. One of the most popular uses of the Internet is for research, he says, so running an additional ad along the bottom of the screen is pointless if it's not relevant to the topic of search.

"People have this conception that the Web has to be like TV, because it's a screen, so they keep trying to come up with ways to make it a new kind of TV," he says. "But advertisers don't want another medium that is demographically targeted and can't really be tracked in terms of the real impact the ad has on the user."