I've got an Audible credit I need to use and am looking for suggestions in the Sci-fi/Fantasy genre.
What I already have:
Wheel of Time
Pretty much everything avaiable for David Eddings
Cold Fire Trilogy
Sword of Truth
All the Xanth Novels
Incarnations of Immortality
Everything by Brandon Sanderson
The Inheritance Cycle
The Complete Hitchhikers Guide to the Galaxy
A Song of Ice and Fire
All the Dresden Files
Everything by Stephen King
Everything by Mercedes Lackey
Since you like fantasy, the first Malazan book, Gardens of the Moon, was recently released as an audio book.
Oh I've heard good things about Steven Erikson and I haven't read anything by him, unlike Frank Herbert. My only concern with this would be that it looks like there's only one book on Audio out of 10 in the series. I don't really have the time anymore to read physical books so I wouldn't be able to finish the series until they're all on Audio.