The Encyclopedia of Skill Lore, by Linus Winterguest, in 23 volumes (see my review, at left).
The Legend of Valendo, by Illithidus Purgitus Rex. A volume written in Illithid detailing the origins of a being known as "Dawn", and the resultant schism in Mind Flayer society, detailing the origins of the current Underearth War.
Eredave's Journal, by Eredave, "The Ancient Elven Ranger". Details the coming to a place called "The Forge", via a kidnapping by a "Feathered Fowl", and detailing education and adventures in that strange prison-realm, The volume ends abruptly, less than halfway through, but gives enough information to allow a careful student to gain Knowledge (Local) of The Forge (especially the City & realm of Penance), and hints at methods of escape from The Forge.
The CRC Handbook of Alchemy & Physics, by the CRC Press, 51rst Edition. A valuable aid to any Alchemist, and many Sorcerers & Wizards, or others developing the material components of new spells. Has many tables detailing the Materia & Energy Aspects of Material Components, and how they interact, what properties they possess, etc.
An Alchemical Primer, by the Dao Chymical Corporation.
Palantirii, by Aragorn Telcontar. Details the history and use of the "Far Seer" stones of Numinor. Offers plenty of hints on the construction of Crystal Balls with extra powers, to anyone with the
Craft Wondrous Items Feat,
Horizon-Walking: A Planar Primer, by Horizon-Walker. Careful study grants Knowledge (The Planes) to any reader who spends a week acquiring it. Purports to have been written by the developer of the Horizon Walker Prestige Class, and details each of the layers of the main planes, as well as pocket dimensions, the Far Realms, and other such Demi-Planes in brief overview. Even so, it is over 2,000 pages in length (with additional notes by later readers).
Flumphs, by Anonymous. Written in either Githyanki or Githzeri, a rather light-hearted (and technically unsound) look at the race, apparently aimed at children, as a fun diversion. The race comes off as a joke, therein.
Ninjitsu, by Ashida Kim. A manual on Stealth in an unknown language. Once translated, a careful student could probably pick up a few useful pointers for increasing Hide/Move Silently skill, unless their skill is already maxed out.
Kolwynia: The Key That Is Lost!, by Anastas Jack. A volume on an over-arching magical theory (or, more properly, a Meta-Magical Theorem) which claims that ALL magic is based upon calls to certain stars, by their names, and that these names
change over time. Periods (or "Epochs") of Magic are listed, detailing how (and purporting to detail WHY) spells have worked differently are included, as well as a great deal of speculation on predicting these changes, and developing an over-all "Key" to Meta-Magical Theory, which would greatly increase the power(s) of any caster who possessed it... The problem is that the computations involve the use of a newly invented form of mathematics, as well as Elven patience and many lifetimes of computation, or the use of a modern super-computer for about a month (and great programming skill). "ShadowJack" is rumored to have used one to solve the equations, in the pre-history of another realm called "Earth".
The Index, by Anonymous. A volume chained to the front desk. When asked, pages magically flip open to the catalog description of any book in the library, and it automatically updates itself when new books are added (often objecting to the mis-filing of books in the wrong subject areas)! If removed, the information remains. If added to a new library, a new Index is developed, and the old one is kept as an Appendix.
Wako-Chat, by SteveC. An apparently-nonsensical treatise which is actually a story written in words taken from many different (often unknown) languages, by a writer who was apparently insane (or at least indecipherably cryptic). It tells a grandious story about a powerful entity whose name translates as variations of "Bonzai-Cat", "Wako-Chat", etc., and the troubles he dumps upon the heads of a group known as "Players". Some portions purport to be written by the villian, himself! The entirety is... suspect, at best, as the tale is, ultimately, pretty unbelievable!
Stargate: SG-1, by Stargate Command. A set of silvery discs that take some time and magical analysis to be readable, contained within a brightly illustrated case of strange material. These discs contain sounds and images detailing the adventures of an odd group of alien mages in their battles against a race of false gods, calling themselves Goauld, while wielding great forces and a plethora of odd wands and staves, and travelling almost instantaneously about the Universe via "Stargates" and "Wormholes" of unknown origens, created by an even older alien race. The depicted events are nearly as unbelievable as
Wako-Chat!, but could conceivably introduce studious PCs to modern firearms & electronics.
The Holy Bible, by "I AM". The holy book of an unknown, Monotheistic religion, in an unknown tongue, along with some passages underlined, and a few notes, hand-written. The first verse translates as "In the beginning, God created the heaven and the earth.", and the words translated as "beginning", "heaven", and "earth" are underlined, and above them are written words in the same tongue, translating as "time", "space", and "mass", followed by the unknown (and possibly non-sensical) equation "E=mC^2" derived as "m=E/C^2". No meaning is apparent.
Comprehend Languages will give the meaning as "Creation, out of nothing, is possible, presupposing the knowledge and an infinite source of energy."