The hit movie "Star Wars" by filmmaker George Lucas had many iconic elements, and aside from Luke Skywalker's light saber, perhaps no element of the movie was cooler than the X-wing fighters the Rebel Alliance flew into battle. That may help to explain why an actual X-wing fighter prop used in the movie recently sold for over $3 million.

The X-wing was a 20-inch model that was used to film the epic scene where Skywalker and the rebels attack and destroy the Death Star in the movie's final battle. At the time, it was one of the most memorable moments in cinematic history. This was in large part because of the revolutionary special effects Lucas's original production employed to create a "galaxy far, far away."

Another thing that made the Star Wars films so memorable was the aggressive licensing of the franchise to toymakers like Mattel Inc. (MAT  ). The company seized on the popularity of the franchise by making action figures and toys featuring the film's most memorable characters along with their spaceships. Almost any child in the 1970s or early 1980s can remember seeing an entire section of their local toy store dedicated to Star Wars merchandise.

As that generation has grown into adulthood, the popularity of original Star Wars merchandise has grown immensely. Original action figures still in the box routinely sell for hundreds or thousands of dollars, depending on how rare the item is.

It wasn't just toys, either. There were "Star Wars"-themed lunch boxes, Halloween costumes, video games and just about any other consumer product imaginable on the market for decades following the film's original release. With each sequel, a new iteration of toys and officially licensed merchandise came out; and the franchise's popularity never waned with its original fans.

The toys and merchandise still fetch good prices if they are in good condition, and the original props from the movie are almost invaluable. For a "Star Wars" enthusiast, the chance to own an X-wing fighter model that was used in the filming is akin to an art collector getting a chance to buy a masterpiece by Monet or Picasso.

This particular X-wing fighter was presumed lost in 1978. Since then, people have been looking for it, but no one could come up with the real McCoy. Ironically, the missing X-wing had been in the late Oscar-nominated model maker Greg Jein's private collection. In what can only be described as a happy accident, whoever found the X-wing fighter in Jein's garage increased the value of his estate by millions of dollars overnight.

It is only one of four to have been made with working lights and wings that could close or open to create the unique X-wing fighter effect. With its provenance and authenticity verified, collectors around the world lodged insane bids once it went up for sale at Heritage Auctions in Dallas last month. When the hammer finally struck, the final price was $3.1 million.

Movie and sports memorabilia have been popular with collectors for decades, and that popularity seems to be growing along with their value. Some collectors want to buy back a piece of their childhood, while others are in the market strictly for investment purposes. They buy items like the X-wing fighter or a game-used jersey from a popular athlete and hold it while the value appreciates.

Then they sell it to a hard-core collector or another investor who believes the value will go even higher in the years to come. Collectibles have gone from a hobby to a full-fledged alternative investment opportunity for some people.

So, while it's unlikely you have an original X-wing fighter from "Star Wars" in your basement, you can still get in on the collectibles game and have fun while diversifying your portfolio.