I can’t stop looking at the “Iron Man” movie trailers.

My friends, co-workers, even that one guy at my bus stop who tells me to cut it out, that I’ll be sick of the dang movie before I ever see it — everybody knows the all the best scenes are in the trailers. Part of me fears this is true. Still, I can’t stop.

The sight of an airborne Stark in Iron Man armor 3.0, handily thwarting two fighter jets on his sonic tail causes my face to flush, my heart to thump and makes my brain unable to access anything resembling the English language. Technically this isn’t what "viral marketing" means, but that’s an apt description for my affliction.

And these are exactly the symptoms big movie marketers want target audiences to exhibit —preferably followed by obsessively forwarding movie links and nattering endlessly about the movie in chat rooms.

That’s how viral marketing works, and the Internet is the perfect breeding ground. But as marketers attempt to create the ultimate viral Web campaign, they risk burning out the audience before the movie hits theaters.

Happily, this will not be the case with “Iron Man.” How do I know? Because … I just do.

Admittedly, I’m the kind of sci-fi freak who didn’t need to see any "Iron Man" trailer to get my mouth frothing. The casting is spot on: Robert Downey Jr. as the embattled and alcoholic Tony Stark, Terrance Howard set up as the sequel’s War Machine, and Samuel L. Jackson as Colonel Nicholas Joseph "Nick" Fury!

SAMUEL L. JACKSON AS NICK FURY!!! I mean, c’mon!

Still, you needn’t be a Marvel Comics freak to catch “Iron Man” fever. The awesome trailers are enough to get the heart racing without burning out the brain. See, “Iron Man” is the most moderate example of viral marketing among this summer’s three comic book blockbusters.

The word got out about this movie with little more than some cross-branding with LG Mobile and Audi (yeah, like Tony stark drives an Audi). Meanwhile, compared to “The Dark Knight,” with its like, 80 ka-jillion viral Web sites, Edward Norton’s “The Incredible Hulk” reboot is barely an Internet whisper.

Perhaps in an effort to distance the film from the 2003 “Hulk” disaster, the movie’s marketing reps are keeping a low profile. This radio silence can be frustrating to true fanatics, but in this case, perhaps the best course of action.

“The Dark Knight” fans, however, are getting a veritable viral feast served up in cyberspace. For those who don’t have the time to play “Batman” scavenger hunt, the Web site “Known Dark Knight Viral Websites ” thoughtfully compiled links and screenshots to each.

While “The Dark Knight” campaign is awesome, viral Internet marketing can trace its roots to “The Blair Witch Project.” In 1999, this surprise, low-budget blockbuster whipped up the masses with what many suspected to be fake fan chatter in cyberspace — over 20 fan sites popped up before the movie’s release.

“Leaked” clips created an irresistible urban legend appeal, with “Blair Witch” Web rings bandying about speculation that the whole story really truly happened, somebody’s brother had a friend whose cousin’s sister knew the girl in the movie and that it really happened.

Such marketing was cheap and effective, and so as a movie marketing device, viral promotion proliferated — though to varying degrees of success. Case in point: “Cloverfield.”

The recent monster movie, produced by J.J. “Smell My Red Herrings” Abrams of “Lost” and “Alias” fame, told Web denizens too much and for way too long, resulting in a blasé reception of what turned out to be a perfectly serviceable monster movie.

This should be unsurprising to anyone familiar with “Lost,” a show that’s overplayed its viral hand by leaking important plot points (like the meaning of those stupid numbers) without ever adding that info to the actual TV show. This irritated (and perhaps alienated) a lot of hardcore fans.

With “Cloverfield,” Team Abrams created “Slusho,” a faux Japanese beverage that became the obsession of sci-fi geeks everywhere. In the end, knowing all things Slusho turned out to be pretty much an enormous waste of time and energy — the product meant nothing to the plot. What’s more, the movie did a pretty good job telegraphing the lead characters as annoying jerks. You didn’t need to read their MySpace profiles to rejoice in their unavoidable doom. This viral saturation ultimately resulted in an audience exhausted by the extra information, showcasing its irritation in box office receipts (and lack thereof).

In the end, any marketer assembling an online viral movie campaign should take a tip from “Maxim” magazine. There’s something to be said for holding a little back.