I went to see Spider-man 2 yesterday which was a moderately fun film. But (and it's a big But), they got the science so wrong that it's just incredible. There's an awful lot of things that I'm willing to forgive in a comic book film. I can suspend my disbelief enough to believe that a genetically engineered spider can give a man the ability to swing through New York and super strength. I can believe that a scientist can invent artificially intelligent super-strong arms that can take over his brain. Hell, I can even believe that Peter Parker made his suit! But what I absolutely cannot believe is that there are only twenty five pounds of tritium on the entire planet. Tritium is just an isotope of hydrogen (the most common element in the universe). It exists in large quantities on the planet, and it's possible (difficult, but not that difficult) to manufacture it synthetically. A moment's googling (or a basic knowledge of physics) would have revealed this.
This probably wouldn't have annoyed me so much if it had been a throwaway reference, but it's the core of the film – creating a sustainable fusion reaction with tritium. If they had gone for some random pseudo-science power source then that would have been fine, but the incredibly bad attempt at using real science (and reinforcing the already existing fear of all things nuclear) just left a bad taste in my mouth. Which was disappointing, because apart from that, I thought that it was quite a good film (notwithstanding the "with great power comes great responsibility" theme that got rammed down your throat at every opportunity).