Life is unfair to the main character, so he is trying to get even with the whole world. When he gains power, it gets even more downhill: His love of his life is gone, people are after his head due to some misconduct(turning their lives where their sun doesn't shine), and worst of all: heaven and hell rather welcome Armageddon into their arms rather than letting him into their domains.

Or something of standard: Main character is just pissed off at everything and gets into trouble with his teacher or boss despite being good at what he do.

[img]http://i30.photobucket.com/albums/c303/jasonpark1987/0c01ca55-eed4-4af9-a361-1d424276fe1e.jpg[/img]

I think Neon Genesis Evagelion some what fits.

Protect Independent Film
All that we see or seem Is but a dream within a dream. - Edgar Allen Poe

Imagination rules the world. - Napoleon Bonaparte

All men are born with a nose and ten fingers, but no one was born with a knowledge of God. - Voltaire

hhmmm. Death Note could follow that. its a really deep manga, and the anime is great too. they follow each other pretty well.

anway, quick overview, main character starts out wanting to help and change the world because he thinks its rotten, and then he really goes downhill. i don't know if that's what you really want, but its a great manga either way!

one of these might work...

Gantz
Holyland
Nana
Himizu
The Breaker
Vinland Saga
Jisatsutou
Sidooh
Ciguatera
Real

[img]http://img40.imageshack.us/img40/4158/1205047355313.gif[/img]

Would it be more important that they're pissed off w/the world, they are genuinely miserable or their life goes downhill?

Bit of each:

Battle Royale, though it's kinda due to situation
Loveless
Angel Sanctuary
Übel Blatt
Freesia

Maybe from a female high schooler point of view, Life?

[img]http://i221.photobucket.com/albums/dd199/vivharv/Gokusen-1.jpg[/img]

Junk - Record of the Last Hero

my girl the seinen not the shojo, he's pretty miserable. saikano is depressing, as well as another one the author wrote.

i like comics as well
don't kill me

I second Death Note and Angel Sanctuary, they both fit but in terms of life being unfair to the main character and Heaven and Hell and Armaggeddon I'd say Angel Sanctuary is a better choice, though Death Note is amazing as well. Not read all of Gantz but I agree that it might suit your needs. I will also add

07 Ghost ~ Life is unfair, revenge, people after him.
Nabari no Ou ~ Great power, unfair, people after him.
X ~ Life unfair, great power, end of the world, people after him.
Chronicles of the Cursed Sword ~ Great power, lost love, people after him
Vampire Juujikai ~ Great power, lost love, people after him, end of world.

The pen is mightier than the sword...and considerably easier to write with.