Science fiction is littered with time machines of all different shapes and sizes, with a litany of different rules and regulations that may or may not need to be followed if the protagonists want to avoid blowing up the universe.

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Some of these time machines make perfect logical sense (as far as time travel goes). Others, not so much. Either way, the genre provides huge opportunities for creativity, and some of the time machines that have been dreamed up by writers aiming for absurdity, realism, or just plain old awesomeness have inspired audiences and stood the test of time (which is rather fitting when you think about it).

TARDIS ('Doctor Who,' 1963)

11th Doctor TARDIS interior

The TARDIS, a charmingly retro, infinitely-bigger-on-the-inside time-traveling space-ship that also contains a library, a swimming pool, and the most stylish wardrobe in the universe, is so self-evidently wonderful that it’s something of a challenge to lay down in words just how much it deserves to be on this list.

Possibly the one thing that makes the TARDIS (that’s Time And Relative Dimension In Space if you were wondering) even cooler than its initial premise makes it sound is its total and utter inability to be any more than vaguely accurate in landing where its pilot wants it to go. You were aiming for 1979? Well, I hope you enjoy 1879. Did you want to go 12 hours into the future? Oh, we’ve popped ahead 12 months instead. Oops! But in the end, it’s hard to complain – this erratic approach to time travel ensures that excitement and adventure are never in short supply.

The Box ('Primer,' 2005)

The Box from Primer

When entrepreneurs Aaron (Shane Carruth) and Abe (David Sullivan) accidentally invent a time machine in their garage, the exciting opportunities are as numerous as the unfathomable dangers of meddling with the space-time continuum. Primer is a cerebral and anxiety-inducing demonstration of how time travel might function in real life — and even that results in deteriorating doppelgangers and alternate timelines galore.

To say that Primer is complicated is an understatement, but that’s all a part of the film’s cool factor. Our protagonists are a pair of nerds who built their time machine between their day jobs, and it's every bit as clunky and unglamorous as that setup suggests. Even the time machine’s name — unceremoniously referred to as "The Box" — acknowledges that there is nothing slick or stylish about this operation. As Aaron and Abe discover, time travel is ramshackle, scary, and very dangerous, and Primer’s take on it is so thoroughly unique as to be one of the coolest portrayals thereof that sci-fi has ever seen.

Heptapod Language ('Arrival,' 2016)

Heptapod Language

The Heptapods are an alien race whose written language implies they don’t experience time linearly as we do, but instead (to borrow a term coined by another time traveler) as a big ball of wibbly-wobbly, timey-wimey stuff. When linguistics expert Dr. Louise Banks (Amy Adams) begins deciphering the language, she also learns to perceive time the same way, allowing her to travel into the future and gather the information that might end up saving the world.

Alright, so this isn’t exactly a machine, but it is still a tool that can be used to travel backward and forwards along your timeline. More importantly, it’s quite possibly the most innovative and philosophical method of time travel ever presented in fiction — its exclusion from any list about time travel would be borderline criminal.

Phone Booth ('Bill & Ted’s Excellent Adventure,' 1989)

Bill and Ted's Excellent Adventure
Image via Orion Pictures

In the year 2688, a society inspired by the bodacious philosophies of metalhead slackers Bill (Alex Winter) and Ted (Keanu Reeves) discovers that their two heroes are in great danger, and send back a time machine in the form of a telephone booth to help them get an A+ on their high school history project.

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There’s nothing particularly novel about this machine. It’s a pretty simple affair — just dial the right number and off you go. It’s very straightforward. It’s also just extremely cool. Bill and Ted surf a series of psychedelic wormholes known as "The Circuits of History" as they crash from one time period to another, encountering historical figures and generally being a nuisance. The Phone Booth is undoubtedly one of the gnarliest time machines in history, if only because our protagonist’s nonsense would be impossible without it.

Hot Tub ('Hot Tub Time Machine,' 2010)

Hot Tub Time Machine

It’s hard to imagine how a time machine could get much cooler than this. It's a hot tub, for crying out loud. The fact that "Chernobly" (a Russian energy drink of questionable legality) can be applied to the control panel to open a swirling vortex back to 1986 (or, in the sequel, forward to 2025!) is just the icing on the cake.

The functionality of time travel in Hot Tub Time Machine is also pretty interesting, with the travelers appearing to everyone but each other just as they looked back in the 80s. This setup incentivizes the protagonists to try and change as little as possible, each agreeing to re-enact their past exactly to avoid destroying the future. None of them do, of course, but it turns out the fabric of space-time is a lot more durable in this franchise than in others. Which is exactly what you’d expect. Who could imagine that a time machine built out of a hot tub would want to ruin anyone’s fun?

The Capsule, ('Twelve Monkeys,' 1995)

Time machine from Twelve Monkeys

In the year 2035, a deadly virus has wiped out most of the population, and survivors have been forced to live underground. Humanity’s last hope lies with James Cole (Bruce Willis) — a convict selected for a special mission to return to when the virus began in 1996 and bring a sample back to the future for the creation of a vaccine. The time machine in this movie is the stuff of nightmares; a mash of steel girders and dirty scaffolding the size of an aircraft hangar that requires a whole crew to operate.

Worse still, it’s liable to drastically overshoot and land its occupant adrift in history. On his first journey, James lands in 1990 — not 1996 — though all things considered, that’s an unqualified victory, seeing as other misfires have propelled travelers as far back as the Middle Ages. Plus, it turns out that time travel isn’t easy on the mental faculties. James’ sanity (indeed, whether he’s even a time traveler at all) is an opened-ended question, with the movie only dropping the bare minimum to assure us that Cole probably is from the future, and the dystopic wasteland of 2035 is probably not just a paranoid delusion. Time travel is a messy business in Twelve Monkeys; unreliable, disorientating, and utterly fascinating.

DMC DeLorean ('Back to the Future,' 1985)

DeLorean about to time travel

“If you’re gonna build a time machine into a car, why not do it with some style?” asks Dr. Emmett Brown (Christopher Lloyd), the eccentric genius behind Back to the Future’s eternally thrilling time-travel icon. And why not? After all, the DeLorean, with its futuristic wing doors and pulsating flux capacitor, is one of the most recognizable time machines in the history of the genre, and it’s far from a mystery as to why.

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This thing was surely custom-built to be as enthrallingly cool as possible. Powered by plutonium? Check. Flying abilities? Check. Only operational at a recklessly high speed? Check! Only the most joyless of cynics could resist the sheer excitement of seeing the DeLorean sparking and flashing as it builds up momentum, followed by the blast of neon energy and the fiery trail it leaves behind.

The Pod ('Timecop,' 1994)

Pod from Timecop

There is a gleeful absence of logic surrounding Timecop; it’s established more or less immediately that travel to the future is impossible because “it hasn’t happened yet,” although traveling from the past into the future (considered by the protagonists as the present) is totally groovy. Well, that makes absolutely no sense, although it might stand up a little more than the movie being largely set in the ‘near future’ of 2004 while Jean Claude Van Damme still rocks a mullet.

But this is fine anyway because what we get out of it is a rocket-powered time-pod-go-kart whose rules make as much sense as the plot. How does this awesomely impractical piece of tech work? Well, you strap yourself in, the pod propels you toward a concrete wall at breakneck speed, and reality wobbles around you, vanishing both the pod and its occupant. You then materialize in the desired time without the pod, which you also don’t need to return home (pressing a button on a little remote control seems to do the trick). Naturally, the question of quite why we need the pod in the first place is likely to be raised, especially considering the film confirms at least two people have been killed during the (apparently unnecessary) process of slamming a metal cage into a concrete wall at high speed. Well, the answer is this: because it looks cool as hell. That’s why.

The Map ('Time Bandits,' 1981)

Time Bandits map

The Supreme Being (Ralph Richardson) has noticed there are a few spots in a reality where the fabric of spacetime is fraying around the edges. He employs an unruly group of miscreants to repair the fabric, but they quickly realize it would be far more fun to simply steal the map that indicates where the holes in reality are and use them to traverse history and steal whatever treasures they come across.

Whether it’s an Ancient Greek palace or the RMS Titanic, time portals show up in the most unexpected of locations, though they never seem to be far from lunacy and disaster. If you’re watching a time travel movie written and directed by ex-Monty Python star Terry Gilliam, you shouldn’t expect any less than total unhinged surrealism, and that’s exactly what Time Bandits delivers.

The Time Machine ('The Time Machine,' 2002)

Time Machine 2002

Dr. Alexander Hartdegen (Guy Pearce) is an inventor from 1899 whose fiancée is murdered by a gunman. He works tirelessly for years to create a time machine that will allow him to travel back and save her, but when his attempts to change the past repeatedly fail, he decides to travel into the future to see if scientific advancements can help him set things right.

Dr. Hartdegen’s time machine is a finely crafted beauty — all swirling rotary blades and extravagant bronze piping — and the visuals of time travel are completely mesmerizing. The machine becomes enveloped in a bubble of energy, allowing the traveler to watch as history passes rapidly around them. The sun continuously loops overhead as days, then weeks, then months, and eventually centuries pass within seconds, and civilizations rise and fall within the blink of an eye. Overall, The Time Machine received mixed reactions from critics, but it certainly proved one thing — if you’re going to combine time travel with the aesthetic of Victorian engineering, you can rest assured that the results will be incredible.

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