"Frostflower and Thorn" by Phyllis Ann Karr -- My favorite swords and sorcery fantasy, which incidentally has a fairly explicit rape scene.

"The Idylls of the Queen" by Phyllis Ann Karr -- my favorite Arthurian novel and favorite mystery, starring my favorite knight, Sir Kay.

"The Final Reflection" by John M. Ford -- My favorite science fiction novel, set in the Star Trek universe, but before the Enterprise was built, covering decades of Klingon history, since invalidated. A book about chess.

"How Much For Just the Planet" by John M. Ford -- Robert Asprin ("Another Fine Myth") writes funny stories, but this one made me laugh so hard I couldn't breath. A must for anyone who's ever even heard of Gilbert and Sullivan.

There are others, but I'd list them by author, rather than by story.

Probably the best story you're never going to get to read is "The Fire Inside" by John Faylo, who can't get it published. Hard science fiction, set in a Machiavellian future where North Americans, Asian Indians and Japanese are struggling for control of known space. A love story, with a lot of religious/philosophical overtones, and both a hero and an anti-hero. Good stuff.