Redshirts I especially liked. It deals with characters aboard a starship realizing that they were characters in a 21st Century TV series...a bad one...where crewman were killed indiscriminately simply as a plot device, giving their lives no meaning. A number of them then find a way to get in touch with the show creators. No more lest there be too much spoilerism.
The other book is Napoleonic history. The Battle of Jena-Auerstadt is one of the Emperor's greatest victories. This book deals pretty fairly with it, but somehow left me cold. Sorry.