Recommend me some hardcore sci-fi novels

Hey, I'm looking for interesting novels of science fiction, but on the darker side. You know, Asimov and all it's pretty good, but they maybe are too much good little boys.
 
Do you know some modern sci-fi works where they emphasis on the science a little more?

You've probably read Ender's game so but if not jump right in there followed by Ender's shadow. They're two of the best reads I've ever had.

Yep, Ender´s Game is the one, if you haven´t read it yet. But I´ll be curious to hear more suggestions. A good gritty sci-fi novel would be great right about now.

I'll third Ender's Game.
 
Also - Bio Of A Space Tyrant (Piers Anthony)

Come on guys, Dan Simmons' Hyperion series!
Hyperion / Fall of Hyperion / Endymion / Rise of Endymion 
 
While I thought Ender's Game was fine, I think it might have been built up way too much for me by the time I read it and I didn't quite get all the hype.  

You want dark, then you can't ignore Richard K Morgan's Takeshi Kovacs novels.  Hard-boiled sci-fi/cyberpunk, with massive splattering of violence.   My pick for awesome dark sci-fi.  One of my fave series ever.  

Peter F Hamilton is an epic sci-fi writer, but I' not sure he's dark enough for you.  Though I absolutely adored the Commonwealth Saga, and the follow up Void Trilogy.  Epic interstellar space opera, with a host of memorable characters, so I'll suggest that too.

Honourable mention goes to Leviathan Wakes by James Corey.  Quite dark in tone, reminded me a lot of the Dead Space video game series, with a bit of a horror feel.  Good pacing, with a nice political backdrop.  

Check em out, see what you think.  

Use Of Weapons, or The Player Of Games, by Iain M Banks.
 
The former is the single best book I have ever read. Ever.

gborland


Use Of Weapons, or The Player Of Games, by Iain M Banks.

The former is the single best book I have ever read. Ever.

A statement like always tempts me to try the book in question. You´ve hooked me. I just ordered the book via amazon (reading the praise for the book there as well). Looking forward to reading it and maybe discover a new author.

Maybe not from the darker side, but Rendezvous With Rama by Arthur C. Clarke and Ringworld by Larry Niven are classics.

I'll second Ringworld.
 
James P Hogan's Giant's series is up there as well.

If you want a science focus then read anything by Stephen Baxter.  Especially 'Ring'.  Another hard read is 'Queen of Angels' by Greg Bear.  Baxter and Bear both have some very interesting books.  They aren't always the easiest reads but if you want real hard sci-fi they fit the bill.  'Queen Of Angels' is probably just about the most complicated and difficult book I've ever read.  It was worth it though if you stick with it.
 
 

For cyberpunk - and a great look into some things that are already happening today:
Snow Crash - Neal Stephenson
http://en.wikipedia.org/wiki/Snow_Crash

The Forever War is a great one.

A Memory of Whiteness by Kim Stanley Robinson
 
He wrote the Mars novels.
 
Killer book.

     How about some hard science fiction with a medieval, atmospheric feel?  George R.R. Martin's DYING OF THE LIGHT will suck you in.
     Imagine a world drifting for millions of years through empty space until it encounters a group of supergiant stars engineered by an advanced civilization long since disappeared. Imagine if the people on nearby worlds decide to convert it into a garden world for a century-long celebration.
     Imagine a young man getting a "call" from a long lost love....
     Trust me on this one. You won't want to put it down!
 
 
(edit): Despite the novel's dark fantasy feel, it is most definitely a hard SF novel.  It'll fill that hole in your soul, believe me.