When Eric Cartman first opened Cartmanland on "South Park," he made one thing very clear to prospective patrons: "It's the best theme park in the world, but you can't come!" Although his original plan was to keep his park empty so he could avoid lines, it generated such a huge buzz that everyone wanted in.

This is the driving principle behind the secretive viral marketing of today's films. "This movie is going to be so cool, you can't see any part of it." It's this philosophy that studios today employ to generate excitement for an upcoming release, despite the fact that the film doesn't come out for a year and a half, and you're generally watching about three seconds of actual footage.

Take the original teaser trailer for "Pirates of the Caribbean: The Curse of the Black Pearl," which featured five seconds of a skeletal foot walking on the ocean floor. This was pretty ineffective since it left everyone confused: "Wait they're making a movie out of that Disney ride? What the hell"?

Another example of a teaser that's pretty terrible is the "Transformers" preview, released almost a year before the film's release. A narrative explains how the latest Mars rover didn't actually crash and, sure enough, the shadow of Megatron comes along to stomp the life out of it. It's incredibly lame in execution, but the appearance of the "Transformers" title at the end was enough to send shivers up a few die-hard fans' spines.

But now, things are going a step further. It's not enough to have just a teaser trailer - you have to have an entire viral marketing campaign to go along with it. Sometimes this works, sometimes it doesn't.

Two notable examples are available right now: J.J. Abrams' "1-18-08" and Christopher Nolan's "The Dark Knight." Guess which one works, and guess which one pisses you off. If you've ever seen "Lost," you probably already know the answer.

Abrams is the king of making you want more. Three seasons into "Lost" and we're still wondering what the hell is wrong with this island. And now, his movie is so secret, it doesn't even have a title. That's right, it's just referred to as its release date because he apparently couldn't generate a name that wouldn't give the entire movie away. Really, he's just doing this for the buzz it creates. It may be working, but it's still annoying as hell.

"1-18-08" appears to be some sort of monster movie judging by the teaser trailer, where a Godzilla-esque screech is audible, shortly followed by the Statue of Liberty's head bowling down Times Square. Abrams has set up a number of websites with "clues" about the film, including one with moveable photographs that you can flip over to read messages on the back that don't make any sense. And if you wait six minutes on the site, you get to hear that Godzilla scream again. I've had the site open while I've been writing this, and it just now freaked the hell out of me when my computer started screaming like the devil.

Another site has a short video of a girl saying goodbye to a guy who's leaving. The video ends with a revelation of her bladder infection once she thinks the camera is off. Is that it? Does the monster have a bladder infection? Is that what you're trying to tell us, J.J.? Clues only work when they actually mean something, and I will bet my life that if you spent 72 straight hours putting together all these bits and pieces, you would maybe, maybe discover that the monster is a giant polar bear made of smoke or something J.J. Abrams-y like that. There's creating suspense by being secretive and there's just being an asshole.

Compare this with "The Dark Knight," which strings you along with little candles along the way, giving you a glimpse into the forthcoming film. The producers have also set up numerous websites, one of which promotes Harvey Dent running for political office. Another is full of the Joker's maniacal laughter if you highlight the entire black screen. The one perhaps most widely circulated is the site that, after a little digging, becomes a picture of Heath Ledger as the scar-faced, clown-painted villain himself.

As it draws closer to springtime when Batman returns, screenshots are leaking slowly. Just enough so people are excited, and not enough so it ruins the plot. And the trailer? The Batman logo. With talking. For 30 seconds. It's minimalist but highly effective, especially when you hear the Joker laugh for the first time. Now that'll send real shivers up your spine.

And as the crowds eventually started streaming into Cartmanland, so too will audiences flock to "The Dark Knight." "1-18-08," however, may find us lost in the theater, since they don't even know the name of the damn movie.

- Tassi only reveals bladder infections when off camera. E-mail him at