4. The Point of View Gun (The Hitchhiker's Guide to the Galaxy)
If you can't flashy-thing someone's memory away, why not at least make them see things from your point of view? The Point of View Gun, introduced in the 2005 film version of The Hitchhiker's Guide to the Galaxy, accomplishes just that: You fire the gun at someone, and suddenly, he understands exactly where you're coming from.
Before you get too excited, though, take note: The gun won't work on just anyone. According to the movie, it was created by the "Intergalactic Consortium of Angry Housewives," whose members were fed up with their husbands' lack of empathy. As such, the weapon works only on men.
On second thought, maybe we shouldn't bring this thing into the world.
5. The Bond Watch (various James Bond movies)
Oh, come on: We couldn't possibly make a list of must-have movie gadgets without including a couple of 007 classics. And if there's one quintessential Bond item, it's gotta be the magnetic Rolex watch.
Bond's watch has done a lot of impressive things over the years. It's sawed through ties, disarmed mines, set off bombs, and even unzipped ladies' dresses.
Hey, it's Bond -- give the guy a break.