What is your heroic ideal?

[Eorl of Rohan]

While typing a reply for the "Which good guy do you least like?",
I realized that I seemed to have a preference for certain type of characters in LOTR.

Boromir, Denethor, Turin, Feanor, Hurin, perhaps Maedhros.

I am not quite sure yet exactly what they have in common except that I like them;
(They died? No, wait, Maedhros didn't die. Hm. I don't know. Someone help me out on this one?)
but I think somehow they reveal my thoughts on what an ideal hero should act like.

So tell me,

What kinds of characters do you think of as 'heroic' in Tolkien's works,
and what does that tell you about your concept of heroic ideal? What makes a character a hero?