And not all of the books are out-of-this-world bodice-rippers! I added my favorites to the list: the Liaden Universe books by the team of Sharon Lee and Steve Miller--a dozen in the series and still growing; and the Esmay Suiza and Vatta's War books by Elizabeth Moon top the list. There are others. I have added these to the Dirt Poor Book Shop: Obscure Gems, with a list to many others. Here are a few samples. Enjoy!
A blog on Amazon is well worth viewing, and here is a forum on the topic.