My primary reader is now A Sony which I am very happy with. Plays View from the Veranda and the like when I'm not in the mood to read.
I did have a Kindle app on my smart phone but it died with my phone and the PC version seems to have gone with it to my dismay so there are a couple of interesting books whose details aren't easily found again..
The following free ebooks are some of the ones I have enjoyed. They are all available in epub or pdf but some are also available in Kindle.
Cavalry by Lewis Edward Nolan
Memoirs of W T Sherman
Tin Army of the Potomac
Service with the French Army in Africa by Philip Kearny
Adventures of the Connaught Rangers by William Gratton
Commentaries on the Punjab Campaign 1848-49 by A Lawrence.
The Mexican War by an English Soldier.