This idea was developed in my "Tales by the Fire" thread, originated by OvShit and Graeldragon:
http://www.havenandhearth.com/forum/viewtopic.php?f=5&t=17725
Some have proposed that people would be able to "teach" other players recipes; if one player doesn't know how to make something, such as a sausage, because he hasn't butchered a bear, another player who has butchered a bear, and has access to the sausage recipe, can write that recipe down and give it to the other player, who will then study it and learn the recipe themselves.
I have a different idea, however.
My idea is that, instead of writing a recipe down, a player would "write" objects down in handbooks (giving them familiarity with objects instead of recipes themselves), and instead of learning it by studying it, a player could only get temporary access to the knowledge while a handbook is equipped.
Let me elaborate, a bit.
A player would begin by creating a Blank Book with 10 parchment, 3 leather, and 2 yarn. The Blank Book would then be used to craft a Handbook.
Right-click the Blank Book to bring up a "Create Handbook." Upon selecting that option, an interface will appear. On this interface would be three slots in which to place items (you wouldn't have to occupy all of the slots); the items you place in those slots are the items that the handbook will grant familiarity of. When you've placed all of the objects you want to, you press the "Write!" button at the bottom of the interface; if you have a jar of ink, a quill and a Beautiful Dream for each item, and are familiar with the selected items, you will begin crafting the Handbook. The items are consumed in the process.
Voila! The Handbook, a 3x3 item, has been created! If you want to check which items are "in" the book, just right-click it and select the "Examine" option that pops up; an interface similar to the creation interface will appear, sans the ability to place items. It will show you what items the book "holds."
To "use" the Handbook, simply equip it to one of your hand slots; it only occupies one hand. After having done so, your character will gain familiarity with the items inside, and thus be able to craft objects requiring them, as long as he has the book equipped; when the Handbook is unequipped, your character will lose familiarity with the items if he had not "learned" them naturally.
Questions? Comments? Flames?