Another guy I was thinking of is Kenny Broad, extreme cave diver, venomous snake hunter, and one of two to be named 2011 "National Geographic's Explorer of the Year."
He's currently working on the Blue Holes Project, a study of submerged caves - found both on land and in the sea - which are among the least studied and most threatened habitats on Earth.
This is more in keeping with my interests in cave systems and probably more of a personal one to be honest. But still, worth putting it out there.
A man may die
Nations may rise and fall
But an idea lives on forever.