I am rather fond of the Conquerors Trilogy, but it has been so long since I read it. I found the trilogy at my local library when I was looking for more of Timothy Zahn's Star Wars books.

I thought the Thoma\s Covenant stories were incredible as well.  Not exactly space opera as originally suggested--great fantasy though.

Great list, Mumblefratz.  I was surprised at the absence of Gene Wolfe from your list, although perhaps you've read him but don't own the books.  I have to second Sinperium's recommendation above.  Wolfe writes beautifully, although if you're looking for space opera I'd go elsewhere. 

Wolfe's Book of the New Sun, Book of the Long Sun, and Book of the Short Sun take place in the same universe and are related.  My second favorite series is his Soldier series, Soldier of the Mist, Soldier of Arete, and Soldier of Sidon.  The protagonist is a Roman soldier who forgets everything every night, so that in the morning he has to read a scroll to learn who he is and what he's trying to do.

In addition to the others listed, I'd recommend C. J. Cherryh's Faded Sun trilogy. For those of you unfamiliar with her, her real last name is Cherry, and her publisher convinced her to use the pen name Cherryh, since he thought that no one would take her seriously writing under her real name.

The Faded Sun trilogy is my favorite work of hers.  Mumblefratz also listed Downbelow Station, which is very good, and some of her Chanur novels.    For fantasy, her Morgaine series is pretty good.  I'd stay away from her "Russian stories" (Rusalka, Chernevog, etc) and her "Heroes in Hell" novels - in those I got the distinct impression that she'd started writing like she was getting paid by the word.

well, the 'best' have been given.

here are the worst...   Anything L Ron Hubbard or Shatner.

The Dragon Lance books have a cult following (guessing @ 15-20 books in the main story line, with countless numbers of side stories/books), there was talk of a dragon lance mod for wom but perhaps it will be made for FE

Can i suggest the Deathstalker series by Simon R Green. They are both Sci Fi and Fantasy in one, a 9 book series written in the same style as Star Wars etc etc. Humor, violence and character all in one. Well worth the read.

http://en.wikipedia.org/wiki/Deathstalker_(series)#Deathstalker_Prelude

Fantasy.

Recently read two sword&sorcery style series, Codex Alera by Jim Butcher, and Keeper of the Swords by Nick Perumov. Particularly the first is worth reading if you feel like some guts&glory rather than epic themes. Keeper of the Swords is so filled to the brim with fantasy elements - if A Song of Fire and Ice is on one End (very few fantasy elements), and Tolkien's universe is somewhere in the middle, the Keeper of the Swords is as far as you can go in the other direction.

Also, R. Scott Baker has two great series in one world, Prince of Nothing and The Aspect-Emperor (Aspect-Emperor takes place 20 years after the first series, but many characters are still there - the last book hasn't been written yet though). I think no author has chilled me to the bone like this one has - not through scary elements or suspense, but with philosophy and cold, hard logic. There is an "adult" presence in these book.

(war is a big part in Codex Alera, and both the series by R. Scott Baker. Faith is a big part of Baker's books, but not in a bad way)

Patrick Rothfuss has a trilogy called the Kingkiller chronicles, and they're absolutely worth reading, but the last one isn't out yet. Perhaps unique for the genre, the series is (so far) written almost completely (99%) from the viewpoint of one character, although technically the story takes part in both the past and the present. It really feels like you're reading a fairy tale almost, but obviously with far more serious attributes. Since it's from one perspective, and the books are fucking long, the story feels extremely epic as you get to experience the character growth of primarily the main character.

This series is a classic IMHO. There are eleven books and if you like dragons and controversy this is it. Be sure to read from book one. This way you'll get the gist of their history, 2500 years worth. 

The Lensman series by E.E. "Doc" Smith. 6 actual books in the series. Very old and classic space opera. If you want to go nuts finding them, the Perry Rhodan series, of which most are in German only. Only 6,000 or 8,000 books in length.

The Dragonrider series is excellent, and Anne's son has taken over the series.

I cannot second the recommendation of David Weber's Honor Harrington books strongly enough.  Easily some of my favorite sci-fi books! 

Minor nitpick, Asimov wrote over 200 books

I looked through your list and I think I own about 90% of them. Mind you my own collection must run to 750 books now, and 10 dvds. I always much rather buy a book than a video or dvd, and have for my entire life.