BRP CoC might be, but there is significant wiggle room in CoC d20 insofar as scaling lethality is concerned (as the mighty, mighty, American Badass once demonstrated on RPGnet). Honestly, that's why I prefer CoC d20 to CoC BRP -- it's a much more "all around" horror RPG, as opposed to a one-trick "get crazy and die" job.
Other then that i like WOD or call of cthulu for a Supernatural type campaign with the deciding factor being whether you want the bigger risk to be death or insanity for the players.
GURPS Supers and GURPS Horror. It's the easiest system (IMO) to convert real world observations into game terms. "Let's see, he threw the car 60 feet, so his Strength is ..."
Supernatural: Defintely use either nWoD and adjust the starting points to a slightly higher level(for experienced hunters, people often forget Dean and Sam have been hunting their whole life.) or use Cinematic Unisystem's Angel/Buffy rules
Hero: Probably nWoD w/Second Sight's psychic powers... The people in Hero aren't any better than a normal person except for their (except for Skylar) one ability. Second Sight also touches on the issolation that these types of "heroes" feel in the show. Powers are presented on that borderline between gift and curse, which is how majority of the characters view their powers in Hero.
I'd use Champions (HERO) for Heroes. It'd take a bit longer to write up the characters than M&M, but the extra detail would be worth it. Plus, I like the skill system better for HERO.
For Supernatural, I'd go with Buffy/Angel. As was said earlier, it's what the system was designed for.
For Heroes, my default system would be HERO 5th, probably with liberal use of the Dark Hero supplement. Depending upon who my gamers are, though, I might go with Mutants & Masterminds (for those phobic of anything not related to D20) or some kind of D20 Modern/Urban Arcana/Dark Matter kluge. For those more familiar with Palladium, I'd use Heroes Unlimited.
Despite the merits of other systems, like Underground, Aberrant, or Brave New World, I probably wouldn't use them.
D20 Modern can tell any modern story you want. You just need to get the right "plug in" to give it the right twist.
For Heroes, D20Modern with low level stuff from Charles Rice's Blood and Vigilance.
Supernatural I've never seen but gathering what I can from this thread, I'd lean toward D20Modern using the Shadow Chaser's campaign model or Urban Arcana campaign model, maybe Blood and Relics (again by Charles Rice) or just D20 Modern without any plugins and use various sources to get the feel you want.
Probably the closest system to duplicate the show Supernatural would be (IMHO), Dark Conspiracy. It had a very similar premise, groups of "hunters" (in this case, "Minion Hunters") would combat supernatural foes (although it had a complete different backstory, and was set in 2013).
PCs were generally normal people (there were some rules for psychic powers, and you could also be a alien abductee/cyborg), but just because they were PCs, had a ton more hitpoints than NPCs (who had 20). Had a more gear orientated feel than CoC, as in many cases, it was simply a matter of finding the right thing to shoot the beastie with, and the surviveability factor was pretty high for the most part (because PCs tended to have so many hit points).
Which might be too much for Supernatural. They are probably more successful in that than they aren't, but Dean had to be healed a couple of times from basically terminal injuries
(the episode with the Faith Healer, the finale).
But there were stats for all sorts of critters in the book (and I think at least one critter book for it was published).
Chill would probably work, although I think that's closer to "Poltergeist: The Legacy".
I do think Call of Cthulhu would work as well, although the stats of the 2 brothers would be pretty high, as would their skills (especially their Dodge skill). Yes, CoC is more deadly than the show, but they don't exactly go up against Cthulhu on the show, either. While BRP is a reasonably deadly system, what makes CoC so deadly is the nature of the opposition of the PCs. Whiel CoC does have some non-Mythos monsters in it, you would probably have to make stats up for a lot of things, though.
d20 Modern would work very well. Menance Manual has a lot of real world paranormal critters in it and there are some in the corebook, too. And duh, forgot the Dark Matter supplement for it, which I would imagine have lots of that stuff in it.
Spycraft would need a supernatural/paranormal supplement, really, which I hope it gets, but likely won't.
I'm going to buck the d20 loving trend here and reccomend a different system...
A VERY different system.
the One Roll Engine supports a phenomenal game called Wild Talents. It is a suprisingly gritty superheroes game. it's default setting Godlike is one where at the 1936 olympic games, a Nazi flew in to light the torch. Yes, Flew. Then he delivered a brief speech on aryan superiority, and then took off with a sonic boom.
World war two, with superheroes.
On top of that, the One Roll Engine allows for infinite customization of your super powers. I'm not kidding about this. You want a genius who can plot the trajectory of artillery shells in his head From hearing the sound of incoming shells alone? You can do that. You want to summon a swarm of skeletal fish that can nip and bite at your foes? Done.
Best part, the rules take about five minutes to explain, altogether.
Roll your dice pool, look for matches.
That's 90% of the rules right there.
The default setting of Godlike runs from 1936 clear up to the present day, on a beautifully crafted alternate history, complete with dossiers of notable superheroes and their lives. The amount of humanity displayed by these supers is possibly the most surprising detail. For example, the greatest hero of America, The Indestructible Man, Who could not be harmed by any attack, died of cirrhosis of the liver. Over decades, he drank himself to death.
Arguably the best part, Wild Talents Contains the most detailed chapter on creating your own setting that I've ever seen incorporated in a RPG sourcebook. The presented "Axes of design" are easy to use, and easy to apply to any setting quickly and effortlessly.
