Unfortunately, I never really know what to answer to that question, since I don't know of that many stand-alone novels that are of excellent quality. As you can see from my personal Top 5 (see the blog), other than Guy Gavriel Kay's work, well I'm not too familiar with stand-alone works that deserve much acclaim.
Hopefully this poll can answer that recurrent question. And introduce me to books that are well worth my time! And yours!;) And with the well-read bunch that can be found in these parts, I'm willing to bet that we should come up with a few interesting choices!

By the way, since few people actually followed the guidelines of the last poll (best fantasy artists and book covers), I'm sorry to say that I could not come up with any sort of list. But two names kept returning, over and over again.
Which made the selection of the favourite fantasy artists quite easy. And they are:
Michael Whelan and Jon Howe.
Patrick
www.fantasyhotlist.blogspot.com