Also, there are readers for e-book formats for desktop Linux as well. (They probably require ripping out of Calibre by the roots, though.)
e-book formats are not ideal, but they're a lot better for reading text than PDF ever was. The *readers* are not ideal, but just because the Kindle doesn't do Tex-style autohyphenation (or break on hyphens at all) doesn't mean that a desktop e-book reader cannot.