I sat down some time back and tried to think up the jobs that were most reminiscent of comic-book superheroes like Spiderman. I wasn't really thinking much about LOTR-style heroes, but anyways...
Couldn't think of any good careers as a super-villain, which I suppose is just as well.
The problems with being a superhero are several, but the nearest real-life job I could come up with was firefighter.
Accordingly, I started looking into it as a career. At least in my city, the requirements are tough. Firefighters must be in excellent physical shape (better than a lot of military personnel, though probably not better than Marines), fully certified in emergency medicine (EMT or paramedic, which compares to your babysitting First Aid/CPR class like the alphabet compares to Emily Dickinson) and of course they are taught to handle several sorts of crises, from heart attacks to terrorist attacks.
Sounds good to me... now the trick is to get hired. I'm trying to build up some muscle, because firefighters have to pass a difficult set of physical tests; the written test I'm not so worried about.
p.s. Does anybody know of any other "heroic" sorts of jobs? They don't need to necessarily have requirements like this; I consider my father a hero and he is a trial lawyer, but that's fighting-evil-and-rescuing-the-weak of a different sort. (I thought about being a cop, but I'm not sure I'd enjoy that.)