From 'Back to the Future' to 'Star Trek': 10 Greatest Time Machines

There's a reason we're fascinated by time travel. It opens the door to all kinds of mind-blowing concepts, lets heroes visit strange places -- and maybe even change the future. Case in point: 'Project Almanac,' a found-footage time travel movie centered on a group of friends who discover destiny-altering tech. Before you see the film, check out some of the most memorable -- and ridiculous -- time machines. 

Not only is 'Hot Tub' a funny movie about going back to the '80s, the best joke is that they actually USE a hot tub time machine to do it.

When a sentient probe puts 23rd Century Earth in danger, Admiral Kirk and his crew must go back in time to get what the probe wants: Humpback whales. How do they do this? By taking their stolen Klingon vessel to (naturally) slingshot around the sun, which inexplicably sends them back to 1986 San Francisco. Does it make sense? No. Is it great? Hell yes!

If you tried to build a time machine while living underground in an utterly depressing post-apocalyptic future, it would probably look like the bubble-wrap contraption seen in '12 Monkeys.'

It's one of the most iconic images in movie history: A sudden surge of electricity creates a glowing, purple sphere that melts through metal and stone. At the center is either a naked resistance fighter from the future, or a nude Terminator. The science of the "time-displacement sphere" in 'The Terminator' is never explained, but who cares?

In 'Azkaban,' brainy Hermione is given a "time turner" to help her complete her massive school workload. The magic device is used for other purposes in the film's climax, which sees her and Harry traveling back to set injustices right.

Unlike a traditional time-traveling device, the map doesn't literally transport our heroes, but guides them to the Napoleonic Wars or back to ancient Greece.

This thing looks like how a time machine would if it were invented in someone's garage in real life: Boring. Yet its slapped-together design is part of what makes it so memorable -- and morally dangerous. How could a bundle of wires in a metal case cause so much damage? This inde does a great job at showing just that. 

Sure, Doctor Who may have had the time-traveling call box first, but Bill and Ted have more than earned dual ownership with their movie's phone booth. There's no denying the guys' vehicle has burned itself into an entire generation's psyche. Whoa.

Forget about the miserable 2002 remake -- you don't mess with perfection. The 1960 adaptation of H.G. Wells' classic features a time machine that's designed for maximum comfort and style in late 19th century England. Just watch out for those pesky Morlocks.

There has never been a more iconic time machine than the one built by Doc Brown. All you need is plutonium, a Flux Capacitor and enough road to get this baby up to 88 MPH and -- faster than you can say "Enchantment Under The Sea Dance" -- you're back in good ol' 1955. We wanted one when we were kids, and still want one today.