CYBERSPACE — Under normal circumstances, a 50-something machinist and self-described “blue-collar guy” wouldn’t seem like much of a threat to a tech-heavy industry that generates an estimated $40 billion annually. Nevertheless, online advertisers and publishers are beginning to worry about him.That’s because “Rick752,” an upstate New Yorker, is dedicated to helping other cyberschlubs do away with what he considers one of life’s biggest irritants: online advertising that pops up, pops under, blinks, streams, jumps, and twitches on screen, jarring eyeballs and otherwise interrupting a perfectly enjoyable surfing session.

Rick752 spends a hefty chunk of his downtime assembling EasyList (EasyList.AdBlockPlus.org), a compendium of ad-serving sites on the Web and related data. Combined with Adblock Plus, EasyList allows surfers who use Firefox, Thunderbird, SeaMonkey, Flock or Songbird browsers to filter out nearly all advertisements that normally would appear on the Web pages they visit. Both Adblock Plus — which has been downloaded more than 20 million times, according to Mozilla.org, which links to it and encourages its use — and EasyList are free applications, and they’re popular with a growing cadre of surfers, but critics say widespread use of the products could threaten the very fabric of the Web by destroying its economic underpinnings (namely, ads). Currently Adblock Plus has about 4 million active daily users, according to developer Wladimir Palant.

“I started [EasyList] because I was frustrated with getting my computer infected from ads — malware and spyware and all that stuff,” Rick752, who spoke on the condition of anonymity because he fears threats — and, oddly, bribes — from his critics, told the Washington Post. “I kind of went overboard with it. But you have to admit, it’s pretty amazing, right?”

Websites that depend on advertising for revenue have taken different approaches to the growing popularity of ad-blocking software. Some expound a doomsday scenario in which free content will disappear from the Web if users refuse to view the ads that support its delivery. Others, like the political blog Daily Kos and the French photo-sharing site Virusphoto.com, have taken to begging users to turn off their ad blockers in order to maintain the revenue streams that support the content fixes they seek.

“If you use ad-blocking software while viewing Daily Kos, you’re getting all the benefits of our site but we’re not getting any of the advertisement revenue associated with your visits,” Daily Kos tells visitors when it detects they are using ad-blocking mechanisms. As an alternative, it asks them to buy a subscription.

Still other ad-supported sites attempt to block ad-blocker users from viewing their content. PWInsider.com is one of them.

“We are three guys who have no corporate backing and need the revenue that our best-paying ads generate,” Dave Scherer, owner of the pro-wrestling site, told the Post. “We don’t believe it’s unreasonable to earn a living from something that we put 50- to 70-hour workweeks into… For every ad that doesn’t load, we don’t earn the revenue we need to generate to pay our mortgages, bills, etc.”

The sneakiest sites disguise their content as advertising in an attempt to force Rick752 to remove them from EasyList’s encyclopedia of blocked material. Rick752 said that happens all the time, and on some of the biggest sites on the Web. To fix the problem, Rick752 sometimes resorts to white-listing individual content URLs while continuing to block the ones that bear advertising. That’s labor-intensive work, though.

As for criticism that he is destroying the Web, Rick752 is unapologetic. Both he and Palant say advertisers have brought the blocking on themselves by creating ever-more-annoying ads that distract surfers from the content they want to see without giving them anything of value in return. The men hope their systems will force advertisers to back off on the most annoying advertising tactics, perhaps returning to the days of text links and static ads that don’t take up entire pages.

“People hate ads,” Rick752 told the Post. “They really hate ads. We wouldn’t be doing this otherwise.”