When we first heard that the fourth 'Spy Kids' film would have a "4D" title attached at the end, we naturally assumed it was a not-so-clever joke at the number of sequels in the franchise, plus the fact that this one would be in 3D. But then we discovered what that "4" really stood for: Aromascope (aka Smell-O-Vision).

When 'Spy Kids: All the Time in the World in 4D' is released on Aug. 19, viewers will get a chance to actually smell the movie. Cards loaded with eight different scents will be handed out to those attending both 2D and 3D screenings.

While we're sure that Rodriguez will make good use of this "fourth dimension," it got us thinking: What movies would we not want to smell?

'Jackass' Franchise
Just thinking about the smells in these films is enough to make you sick. Among some of the odorific pranks: going to the bathroom in the middle of a hardware store, being thrown around in a Porta-Potty that's attached to a bungee chord, puking after snorting a line of Wasabi at a sushi restaurant, that horse scene (NSFW), etc.

'Days of Thunder'
Sure, the 1990 blockbuster had plenty of cool special effects (for the time, anyway), but do you really want to sit in a movie theater and smell burning rubber, oil and gas coming off a pack of race cars? Neither do we.

'Dumb and Dumber'
Taking a whiff of what went down in the bathroom after Lloyd (Jim Carrey) fed Harry (Jeff Daniels) a few spoonfuls of ex-lax would be enough to scar our sense of smell for several lifetimes. Plus, the scene in the beginning where the dogs are covered in mustard and ketchup couldn't have been pleasant either.

'The Exorcist'
When 'The Exorcist' was released in 1973, movie theaters provided special barf bags for viewers. And if this film ever ended up using Aromascope technology, they would definitely need them. The scene where a possessed Regan (Linda Blair) pukes green gook all over Father Karras (Jason Miller) is still considered one of the grossest movie scenes of all time.

'Fight Club'
This movie has plenty of glorified fight scenes in basements filled with sweaty bodies and blood. Also, the chemicals Project Mayhem used to build explosives were probably noxious. Not exactly our idea of a sweet-smelling cinematic experience.

'The Nutty Professor'
Eddie Murphy reintroduced us to the power of gas when the Klumps decided to have a fart contest at the dinner table. It was hilarious to watch, not so much to smell.

'Indiana Jones and the Temple of Doom'
Another epic dinner scene. If you like the scent of eyeball soup, cooked bugs and chilled monkey brains, then this would be number one on your list for potential Aromascope movies.

'Alien'
We didn't hear anyone complain about the smell when a creature bursts through Kane's chest, kills him, then escapes onto the ship, but we have to imagine that the odor couldn't have been very pleasant.

'Night of the Living Dead'
Dead people do not smell good; dead people reimagined as zombies probably smell worse. Mix in the fact that they are feeding on others, and you have a recipe for one foul-smelling flick.

'Saw 3'
Yes, all of these movies are pretty gruesome, but this one has liquefied pig corpses. Enough said.