*** PDF Warning ***
One of the authors that I really enjoy is John Dalmas. He has written science fiction and fantasy for a number of years now. Anyway, John is slowly converting his backlist and offering it for free. You can find the first several titles on his web site here:
http://www.johndalmas.com/area/Catalog/
These are free, but there is a paypal donate button on the site. Dalmas (actually his pen name, not his real name) is 84 years old and living on social security these days, so I'm sure he wouldn't turn down any donations that you offer.
I have enjoyed quite a few of his books, but two of my most favorite were "The General's President" and "The Varkaus Conspiracy". I can't wait for those to join his free list, but you can bet that I will be paying for them through the donate button.
The one downside is that Dalmas seems to be releasing them only in pdf format. I have sent him an email offering tips/help if he was interested in exploring conversion to other formats, but I didn't see any response from him. At this time, it looks like I'll have to be happy with the one format that the books are available in (unencrypted pdf), and I will happily take them any way I can get them.
MLH