[headdie]

I found Kim Stanley Robinson's - Mars trilogy a rewarding read
http://en.wikipedia.org/wiki/Mars_trilogy

i will also +1 to the Asimov books

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I am surprised no one has mentioned Frank Herbert's Dune series, all good reads.  His son in conjunction with someone else did a few prequel books and finished an incomplete work started by Frank continuing the series which are worth reading once you finished the original books.

[Scotty]

I've never been able to get more than 30 pages into Dune before I confuse myself out of any motivation to read it.

[PsychoLandlord]

Seconding the First two books of Dan Simmon's Hyperion series, as well as the passing up of both Endymion and it's sequel. I've also heard good things about his Ilium/Olympos books from friends though I have yet to read them myself.

[Mongoose]

I'm suddenly realizing that I've read essentially no great sci-fi works.  (Man, my reading rate in general has plummeted over the past few years, too.)  I'll have to jot some of this stuff down myself.

[General Battuta]

Seconding the First two books of Dan Simmon's Hyperion series, as well as the passing up of both Endymion and it's sequel. I've also heard good things about his Ilium/Olympos books from friends though I have yet to read them myself.

Ilium and Olympos are truly awful. Absolutely execrable. Well -Ilium isn't that bad but is rendered awful by Olympos.

Dune is a must-read. Amazing book, eminently readable, both deep and entertaining.

[Ravenholme]

Oohhhh, How could I forget

Iain M Banks - The Player Of Games, Consider Phlebas, Use of Weapons, Excession, Surface Detail in that order

No love for The Algebraist (or Matter, for that matter)?

[General Battuta]

Oohhhh, How could I forget

Iain M Banks - The Player Of Games, Consider Phlebas, Use of Weapons, Excession, Surface Detail in that order

No love for The Algebraist (or Matter, for that matter)?

I wouldn't start with either of those, honest - they're both a little plodding.

[The E]

I haven't read Algebraist, and compared to the novels I mentioned, Matter definitely loses. It's a good book, certainly, but not as good as those, IMHO.

[esarai]

Wow.  Looks like I've got my work cut out for me.

[Mongoose]

It only came to mind because I just picked up a copy at a used book sale, but I highly recommend Carl Sagan's Contact if you haven't read that yet.

[Nuke]

Seconding the First two books of Dan Simmon's Hyperion series, as well as the passing up of both Endymion and it's sequel. I've also heard good things about his Ilium/Olympos books from friends though I have yet to read them myself.

Ilium and Olympos are truly awful. Absolutely execrable. Well -Ilium isn't that bad but is rendered awful by Olympos.

Dune is a must-read. Amazing book, eminently readable, both deep and entertaining.

dune <3

just stick to the original six, all the new ones are just lame abominations. just today i found a copy of dune messiah at a thrift store. not the best book but its better than those lame knockoffs. been keeping an eye out for god emperor, because thats the one i want to reread.

[Luis Dias]

I've never been able to get more than 30 pages into Dune before I confuse myself out of any motivation to read it.

Blasphemy!! Out with your head!

[Nuke]

I've never been able to get more than 30 pages into Dune before I confuse myself out of any motivation to read it.

Blasphemy!! Out with your head!

cast him out into the desert so that shai hulud may judge him!

[Sushi]

Morning Hard Light,

I suddenly, shockingly realized that despite how much a SciFi and Fantasy fan I am, I am poorly versed in decent titles other than the most easily recognizable works ever.  So I come to you for help.  Could you give me some titles that are an absolute must read?  And hell, even if they aren't in the genres, suggest them anyways.

You mention sci-fi AND fantasy...

Brandon Sanderson is my new favorite fantasy author. The Mistborn series especially is some of the most fun I've had reading books for a long time.

And if you want a recommendation from the old school, I recommend Clarke's Rondezvous with Rama. It's one of my favorite sci-fi stories ever.

P.S. I never really got into Dune either. Read the first book (a couple of times) but was never enthralled enough to try any of the other ones.

[General Battuta]

People keep recommending Sanderson and that other dude Patrick Rothfuss, but I flipped through Warbreaker for a few pages and was really underwhelmed. 

[Zacam]

Not sure if it's been mentioned, don't recall seeing it anywhere, but:

Stephen R. Donaldson; The Gap Cycle

I've been carting them around for -years- now.

[General Battuta]

Oh, he's a really nice guy (and kind of handsome). I had the pleasure of hanging out with him a bit.

I could never get into Thomas Covenant, but I think I started it too young.

[Mongoose]

Brandon Sanderson is my new favorite fantasy author. The Mistborn series especially is some of the most fun I've had reading books for a long time.

I haven't read any of his other stuff yet, but I absolutely loved his original novel Elantris.  A completely stand-alone work of fantasy in this day and age?  It's a rare thing.

[newman]

This.. is a very useful topic. Might be worth renaming it to "recommended sci/fi titles" (or something to that effect) and then sticky-ing it. Though I'm not sure about the policy of stickies in gd.

[Colonol Dekker]

Any good free E-Books / .PDF's i could read on the old dog and bone en-route to work?