Referred to as positron colliders, particle accelerators or unlicensed nuclear devices until halfway through the sequel when they finally gain the name 'proton pack', it seems like a pretty dangerous idea to strap such unproven technology onto the backs of three scientists... and Winston. The people of New York were rightly skeptical of these paranormal investigators, but after they saved the city it would be hard to bear a grudge. There is a lot of technical jargon to wrap your head around when it comes to how the proton pack works; words like cyclotron, protonic reversal and positronic ions for instance. It essentially boils down to an energy stream that can trap ghosts, plenty of witty banter and one of the most iconic fictional weapons in history. Just don't cross the streams...