The Martyr's Mirror
This book is sufficiently known that I will not describe it. For those who may not be familiar with it, it can be summed up as the history of the martyrdom and suffering of the people of God from the 1st century to the 16th. It is a large book, and the downloads are in 3 separate text files, zipped. If you open the files and move them to WORD, they equal more than 2000 pages!
Each file is approximately 750 kb.