Occasionally I run across a book where I wonder what was going through the mind of (a) the author to write such a work and (b) the publisher to actually put it in print.
As an undergraduate I ran across an Old Norse Esperanto dictionary. Here is an utterly useless book, good only in that exceptional case where you want to translate a dead language into an invented one. (I guess the library finally figured out that it was worthless because it is not in the catalog anymore.)
The other one is an English translation of the Septuagint (yes, such a thing actually exists). The Septuagint is simply the translation of the Hebrew Bible or Old Testament into Greek, albeit it was done over two thousand years ago. The Septuagint is worth reading, but anything you would want to consult the Septuagint for, such as word choice or phrasing, will be lost in translation. Yes, there are some interesting textual variants, but they too will be of most use in the original; many of them will simply disappear in translation. So an English translation of the Septuagint is like having an English translation of the Tongan Bible. I cannot imagine why anyone would waste their money buying one.