I was thinking of a new noble, for example a Master Librarian who would be in charge
of dwarves marked with a new job assignment like "Scribe"
Scribes would follow your most talented dwarves in a given job for some time and write a book about them,
this would depend on their observation skill, literacy and the skill level of the dwarf being followed.
Once the scribe is finished he reports back to the Master Librarian dwarf who takes the book
to a library zone to check and assign a quality to it. The books may also be updated as dwarves gain skill instead of having to write a whole new one.
Dwarves who have books written about them would gain status, which would give them a permanent happy thought,
they would lose this if another dwarf with a higher skill level in their field had a better book written about them,
they may even become jealous of the other dwarf.
Dwarves can go to the library and study these books gaining knowledge slightly below the level of the dwarf they we're written about.
The amount of time it takes to learn would depend on the literacy of the dwarf learning it, the scribes skill and the skill of the dwarf
the book was written about. Possibly a teacher may also be assigned to the library, further speeding up the learning process.
Dwarves should also be able to learn skills in their own free time, even for jobs outside those that are assigned to them,
they may also gain happy thoughts from this since it's something they want to do rather than being ordered to do.
Books could also be written about historical events, dwarven romances and other dwarfy things. Reading these books would result in
a happy thought for some time and an increase in literacy skill.
The master librarian would also examine the quality of the books and possibly improve upon them, making
the learning time for dwarves slightly shorter or longer, depending on his literacy skill.
You could have several scribes following different dwarves, but the master librarian
could obviously only improve one book at a time.
He would also keep a detailed record of the happenings in the fort, much like legends mode
but readable during fortress mode play. This history book will give happy thoughts and maybe after some
time will gain artifact status. It would be highly sought after by raiders looking for dwarven secrets,
so the longer you have it, the more raiders would come to try their luck at stealing it.
If the history book was stolen or destroyed, it should have a very bad impact on all the dwarves in your fort
sending a large percentage of them into a depressed mood.
Books could be bought and sold, but selling dwarven books should been seen as a bad thing.
Enemies of dwarves who get their hands on these books either directly or indirectly might gain some bonus damage effect or
defense boost against dwarves, making it much harder to defend your fort, they may also learn how to avoid dwarven traps.
Buying books from humans or elves might teach dwarves how to make weapons, food, brew drinks or any number of items that
would otherwise be inaccessible to them. For example, once a book on scimitars was purchased and the order was given for them to be forged, a metalsmith would go to the library and study how to craft them, it might even take several attempts before a usable scimitar was created.
Obviously books open up the path to magic, but that has been largely discussed already.
Just my $0.02 platinum coins.
Sorry if it makes little sense or is badly written, I'm very tired and if I didn't post this now, I never would.