Time travel is a popular storytelling trope in science fiction movies. It allows for creative plots in which the characters meet themselves, have to fix broken pasts or see what the future might be like. Whatever the case, before they can get to the past or the future, they have to figure out a way how to do it first.
Sometimes it's an accident but more often than not, the heroes have a time travel machine at their disposal. The most usual time travel machine is a spaceship that happens to travel through time, but there have been some pretty weird time travel machines in science fiction movies before. They still work just like the audience would expect, but they look different from most other time travel machines.
5 Phone Booth
Phone booths are no longer as popular as they once were. But just two, three decades back, they were an everyday part of life for many people. That's why it's so difficult to imagine one of them could be a time travel machine. Yet that's what happened in the movies with Bill and Ted starring Keanu Reeves in one of his earliest prominent roles.
The two titular friends Bill and Ted use the booth to travel in time, and they even have a clever system of specifying the historical date they want to visit - simply by punching in the phone numbers. Of course, as all science fiction fans will know, Bill and Ted weren't the first people who traveled in time in a small box.
4 Police Phone Box
Of course, the Doctor Who time travel machine is bigger on the inside, unlike Bill and Ted's phone booth. As such, the Doctor and the companions can comfortably live in it and never get on each other's nerves because of a lack of space. TARDIS, as the ship is known (Time and Relative Dimension in Space) wasn't originally supposed to look like a British police phone box from the 1960s. However, its Chameleon Circuit, which made the ship fit the environment, broke when the ship was masked this way, and the Doctor never bothered to fix it.
Multiple characters point out both in the show and in Doctor Who television movies that it's strange to travel in a ship that looks like a blue police phone box, but the Doctor loves the TARDIS anyway and wouldn't change it for another ship.
3 DeLorean
In comparison to other time travel machines, this one isn't as unusual. It's simply a car, albeit a stylish one, that has time travel components built in it. However, it has become so iconic that it's impossible to leave it out. The DeLorean still fits the profile of a less common time travel machine since it's not a spaceship.
Instead, it manages to blend in well with the environment for the most part, but one major downside is that the characters can run out of gas or fail to start the car just when they need it the most to work so that they could travel in time. Ironically enough, the actual DeLoreans didn't become popular cars in the real world, but the Back to the Future trilogy made them immortal for all science fiction fans.
2 Hot Tub
The prize for the most relaxing way of time travel goes to Hot Tub Time Machine, a movie whose title speaks for itself. It has a feel-good atmosphere and is an ideal science fiction movie for watching with a group of friends who just want to relax...even if they don't have an actual hot tub at hand. The downside of this particular time travel machine is that it can only take its users back to a specific year, to 1986, which doesn't allow for a joyful trip into a distant past.
Hot Tub Time Machine is more of a comedy about a group of friends who get another chance to fix their lives than a pure science fiction movie but without the time travel element, the plot wouldn't work. Those who enjoy the 2010 movie will be happy to hear that it got a sequel in 2015, even though the second movie doesn't have as high a rating as its predecessor.
1 Time-Turner
Harry Potter and the Prisoner of Azkaban (2004) is the only Harry Potter movie that strongly works with science fiction elements thanks to the presence of the time-turner. The time-turner is an unusual time travel machine as it's much smaller and as such, more easily hidden than traditional time travel machines. Time-turners are carefully watched by the Ministry of Magic considering how much damage a person could potentially do with them. Despite that, Hermione gets a time-turner in her third year of studies at Hogwarts because she wants to do a lot of classes and wouldn't be able to be in two places at once without the time-turner.
Of course, Hermione later uses it to both save Hagrid's hippogriff Buckbeak and Sirius Black in Harry Potter and the Prisoner of Azkaban. The time-turners only allow to travel back in time, not forward, so its users have to be careful not to end up in a different past because it wouldn't end well for them. In the end, the time-turners were all destroyed, so Hermione and Harry are the only ones who get to travel in time in the movies.