Much can be said for printed books—the feel and aroma of the paper, the ease of flipping back and forth in them. Much can also be said for digital books—portability, no dusting required, less expensive and sometimes even free, but do you know all the freebie sources? The following list has been whittled down so you don’t waste time with badly constructed web sites or those without variety. My four favorites are listed below, and there are even more. Is there anything better than free stuff?