Unconquerable Sun by Kate Elliott is $2.99 on
Amazon.com
This is the first in a new trilogy based on Alexander the Great's life, genderswapped and set in space.
The Baron of Magister Valley by Steven Brust is $2.99 on
Amazon.com
This is a retelling of
The Count of Monte Cristo set in Brust's Dragaera.
The Abyss Beyond Dreams by by Peter F. Hamilton is $2.99 on
Amazon.com
Set in the Commonwealth universe. Apparently, knowledge of the previous books is recommended.