Science fiction movies have a strange tendency to either go bust or to make it big. While epic space operas may not be everyone’s cup of tea, millions still flock to watch the latest CG creations in theatres.

So TechSmart decided to take a look at the five highest grossing science fiction films ever, not the best mind you, but the most profitable.

(Keep in mind that did not include inflation adjusted and re-released titles such as the original Star Wars movies which were released in 1977 and then again in 1997. Merchandise sales were also not taken into account)

5. Transformers: Revenge of the Fallen

The second instalment in the Transformers trilogy just manages to sneak in at fifth place, proving that being a box office success doesn’t necessarily go hand in hand with being a good movie.

Directed by Michael Bay and produced by Steven Spielberg the movie was met with shouts of glee from kids and Transformers fans the world over, but also negative reviews by critics and old-school Transformers fans alike.

Fans of the series criticized the film for focusing more on the human actors than on the actual Transformers, and we have to agree with them. Shia LaBeouf can’t turn into a jet or a truck, yet he gets most of the screen-time, although we wouldn’t have argued with seeing even more of Megan Fox.

Despite the critics’ best efforts the film went on to become one of the highest grossing films of 2009 raking in an impressive $836 297 228.

(If you want some real Transformers action, check out Transformers: War for Cybertron on the PS3, guaranteed to come with no extra humans.)

4. Star Wars Episode III: Revenge of the Sith

Like all geeks, we here at the TechSmart office pride ourselves on being big Star Wars fans, and it pains us to give this award to Revenge of the Sith when movies like The Empire Strikes Back are ten Taun-Taun strides ahead of it.

But thanks to runaway inflation, Star Wars Episode III: Revenge of the Sith takes the fourth spot in our countdown with $848 754 768 in gross revenue.

The opening sequence of the movie leaves you breathless. Starfighters dodging and swerving while lasers bite at their heels while massive capital ships smash into each other like 17th century battleships.

After that… let’s just say the movie went slightly downhill.

If Hayden Christensen (Anakin Skywalker) wasn’t crying then Natalie Portman (Padme Amidala) was crying. The omnipresent Samuel L. Jackson (Mace Windu) suffered a horribly cheap demise and quality actors started to run low.

The film suffered from a flaw only a prequel can - knowing the story beforehand. We all knew Anakin was to become Darth Vader, Yoda and Palpatine would of course survive and Obi-wan would become the resident hermit of the Tatooine outback.

But we should let up a bit, at least Jar Jar Binks didn’t feature as prominently, although the person who came up with all those Obi-wan and Anakin one liners should be trampled by a run-away AT-AT.

3. Jurassic Park

Do you have a raptor defence plan for your home and/or workplace? Have you ever bolted your door or windows shut in fear of giant lizards? If you answered yes to any of these questions you probably live in Jurassic Park.

Jurassic Park, released in 1993, is categorized as a science fiction thriller film. Although there aren’t any denizens from outer space in this movie, it does fit the genre to a tee.

Directed by Steven Spielberg and based on the novel of the same name by Michael Crichton, Jurassic Park became an overnight classic, and is generally regarded as one of the pioneers of CGI in movies. It left viewers breathless, frightened and checking under their beds for raptor eggs before going to sleep.

The story goes something like this; a wealthy billionaire and dinosaur enthusiast creates a dinosaur theme park on an island close to Costa Rica. As you can imagine, giant prehistoric monsters and child friendly theme parks aren’t exactly a recipe for success, and due to a series of unfortunate mishaps we were soon treated to some spectacular dino chomping scenes.

The film bagged a total of $914 691 118, almost a billion dollars and spawned two sequels. And once again, Samuel L. Jackson suffers a cheap death.

2. Star Wars Episode I: The Phantom Menace.

The Phantom Menace was the first Star Wars prequel to be released, appearing in theatres in 1999. After years of speculation Star Wars fans finally had a new story to fall in love with.

Directed by George Lucas, the Phantom Menace is widely regarded as the best of the prequel Star Wars films. No Hayden Christensen, not as many one liners and the fact that the movie wasn’t shot entirely in front of a green screen gave it the classic Star Wars feel. We had to deal with Jar-Jar Binks though, an alien with an accent that makes Naas Botha sound like Sean Connery.

The Phantom Menace had many great scenes such as the nail biting pod race, the epic battle on the plains of Naboo and of course the best choreographed lightsaber scene of all.

Episode I also had better acting than the other prequels, mainly thanks to Liam Neeson’s role as the venerable Qui-Gon Jinn.

The Phantom Menace managed to rake in another $924 317 558 worldwide, allowing George Lucas to finally start construction on his own personal Death Star.

1. Avatar

Not only the highest grossing sci-fi movie of all time, but also the highest grossing movie ever across all genres is James Cameron’s Avatar.

Single-handedly spawning the current 3D craze in movies, television and games, this 3D and CGI filled film raked in an astounding $2 739 642 667 worldwide.

A large part of Avatar’s appeal was that it was released in 3D and on IMAX, helping to establish the film as one of the greatest visual masterpieces of our time.

Chances are strong that you’ve seen it already, so you’ll know all about the stereotypical characters, the Na’vi and the plot’s more than striking resemblance to Disney’s Pocohontas.

Was the 162 minutes sitting with weird-looking glasses worth it? We think so, and so did millions of other fans. Although we did not go so far as to get depressed because Pandora isn’t real.