The movie industry has always pushed the limits of technology to create those incredible visual effects we see on the big screen. Specially designed cameras, state-of-the-art computers, and meticulous animatronics are just a few of the tools at the disposal of directors looking to bring their vision to life. But over the years, some of the most iconic effects have been completed using much more modest means, including a little paint, some simple prosthetics, and … a sock? Check out how some of Hollywood's most memorable special effects shots were created.

1. THE SPEEDER BIKE CHASE // RETURN OF THE JEDI (1983)

The original Star Wars trilogy utilized nearly every trick in the special effects book to realize George Lucas's vision of a galaxy far, far away. There were detailed models for intergalactic dog fights, stop-motion work for the famous Battle of Hoth, and groundbreaking creature designs for Jabba the Hutt and the other aliens that populated the world. But one of the most difficult sequences to crack was the speeder bike chase from Return of the Jedi.

You would think it was simple: get Carrie Fisher, Mark Hamill, and some Stormtroopers on prop bikes, put them in front of some fake trees, and get filming. Well, the problem is the speed Lucas wanted was nearly impossible to convey with matte paintings or models—audiences needed to see trees whiz by in order to feel how fast these bikes were moving. 

To achieve this, the team at ILM walked through a disguised path in the woods of Cheatham Grove, California with a Steadicam shooting one frame per second. Projecting that footage back at 24 frames-per-second makes it come out—you guessed it—24 times faster. Special effects guru Dennis Muren, who worked on the shoot, estimated the cameraman was walking 5 mph, so when you replay that 24 times faster, you're over 100 mph. When that sped-up footage was projected behind Hamill and Fisher on their prop bikes—along with some clever editing, first-person shots, and even a few models—it made for one of the most memorable sequences of the entire trilogy.

2. THE TORNADO // THE WIZARD OF OZ (1939)

While a tornado might not sound too daunting for today's special effects teams, in the 1930s the crew of The Wizard of Oz needed to get creative to bring the movie's twister to life. Special effects director Arnold Gillespie first tried to film a rubber cone to simulate the tornado, but it was too rigid to be believable. He then took inspiration from the wind socks found at airports and used a cloth muslin sock for the effect. The steel gantry that held the cloth from above the set cost more than the budget for the entire scene, but because of the sock's pliability, it made for a perfect cyclone. To top off the effect, compressed air hoses shot sand and dirt at, and through, the sock, giving the illusion of giant clumps of earth being kicked up in the storm's path.

3. NAZI FACE MELTING // RAIDERS OF THE LOST ARK (1981)

There are a lot of prosthetic heads that have been blown up, mangled, and crushed throughout the grand history of the movie business, but few have been disposed of in more gruesome fashion than the melting face of Nazi Arnold Toht in Raiders of the Lost Ark. For the movie's climax, Steven Spielberg needed Toht's whole head to melt on-screen in a full gory display, and to do this, a gelatin mold of actor Ronald Lacey's head had to be made.

The head was created in different colored layers to get flesh, muscle, bone, and blood in there; then the whole contraption was melted using controlled heat. To get the effect just right, the head was melted gradually, but it was shot at less than a frame per second, so it unfolds quickly on screen when it is projected back at standard speed. Think of it as face-melting time-lapse

4. THE EXPLODING HEAD // SCANNERS (1981)

Even if you've only seen the GIF, chances are you're familiar with Louis Del Grande's exploding head from David Cronenberg's Scanners. For this scene, Cronenberg wanted a prosthetic head to explode without the use of pyrotechnics, since a pyrotechnic explosion would cause a spark or a flash on camera, which wouldn't make sense since the head was supposed to explode due to telekinesis in the film.  

For the actual head, the crew experimented with plaster and wax models before finally realizing that a gelatin mold of Del Grande's head, lined with a plaster "skull," would achieve the desired effect of a real head and skin. The mold was then filled with fake blood, wax bits, and "leftover burgers" to get that gray matter just right.

However, getting the whole thing to explode was another challenge—nothing seemed to work. Well, the best solution is usually the most obvious, and special effects supervisor Gary Zeller decided to get the explosion right the only way he knew how: he sat behind the dummy, turned on all the cameras, and shot the back of the skull with a shotgun. Case closed.

5. WALKING ON THE CEILING // 2001: A SPACE ODYSSEY (1968)

To appreciate the special effects from Stanley Kubrick's 2001: A Space Odyssey, you have to understand where we were as a planet when it premiered in 1968. Not only had we not yet landed on the moon (that would happen the next year); we had never even seen a full picture of Earth from space—that wouldn't happen until 1972. Yet despite that, Kubrick managed to give audiences a vision of the moon and outer space that's so authentic, it has actually become the subject of conspiracy theories. And one of the director's crowning achievements in space photography? Gravity—or the lack thereof.

To realistically simulate life aboard Discovery One, Kubrick paid special attention to the artificial gravity that would have been necessary to help astronauts live comfortably, including how they went about their exercise. In one of the film's most impressive scenes, audiences observe astronaut Frank Poole jogging in the ship's rotating centrifuge, seemingly running upside down at points.

The movie is meant to show the ship's rotation simulating gravity in space, yet to achieve the effect on-screen Kubrick had a mammoth $750,000 set built that would rotate like a Ferris wheel. Actor Gary Lockwood wasn't actually running at all; he was simply moving in place at the same speed opposite the set's rotation. Some inventive camera angles were then used to cap off the illusion.

The other, perhaps more impressive, use of this same technique came when a stewardess is seen seemingly walking upside down while taking a tray of food to the cockpit of the Aries. Despite all appearances to the contrary, the actress actually remained upright the entire time—to an audience, though, she looks to be a 21st-century Fred Astaire. This effect, again, implemented a rotating set and camera that moved along with it.

6. THE RIPPLING WATER CUP // JURASSIC PARK (1993)

By this point, any movie buff knows how the dinosaurs from Jurassic Park were achieved—a little bit of animatronics and CGI and voila!—but what about the movie's most famous non-dino scene: the rippling water cup. It seems simple enough, especially compared to the rest of the movie's mammoth effects, but it took a little Earth, Wind, and Fire to inspire Spielberg to even do the scene in the first place.

On a drive, the director was listening to the iconic funk group when he noticed his mirrors were shaking along with the bass. He then called effects supervisor Michael Lantieri and told him, "We need to shake the mirror, and then I wanna do something with the water." To get the rearview mirror to shake took nothing more than a small motor, but the water was a different story. It wasn't until Lantieri experimented with different notes on a guitar that he finally found the right frequency to get Spielberg's water trembling with the perfect rings.

Recreating this happy accident on set required a guitar string to be fed underneath the truck where the cup of water was being held. Someone would have to lay under the truck and actually pluck the string to get it just right for the screen. In a movie dependent on bringing prehistoric beasts back to life, it was a few water ripples that proved to be one of the more unique special effects problems to solve.

7. THE CHESTBURSTER // ALIEN (1979)

The creature effects designed for Ridley Scott's Alien were a cut above what the sci-fi genre had to offer at the time, but the one moment that sticks out most is the infamous chestburster scene. To get the extraterrestrial fetus to burst from John Hurt's chest cavity just right—and to get a legitimately terrified reaction from the actors along the way—Scott depended on two things: secrecy and a butcher shop.

To simulate a human body, Hurt had to slip underneath a prosthetic body with only his real arms, neck, and head sticking out from beneath a table. Then, the crew filled a fake chest cavity with all manner of animal organs taken from a local butcher shop, along with tiny hoses to spray fake blood when the time was right. This whole time, the rest of the cast was kept in the dark about the scene—the only thing written in the script was "This thing emerges" from Hurt's character's chest.

"This thing" happened to be a rabid alien puppet with sharp teeth, spewing blood and entrails all over the other characters when it finally emerged. The stream of blood was so violent that star Veronica Cartwright passed out when she got a face full of the stuff. This technique of pure shock was Scott's doing, who didn't want any of the actors to "act" scared. He wanted the real deal.