So I've been thinking, these past few years the instruction booklet that used to come with games is now, more or less a thing of the past. For me, it was the first thing I used to thoroughly examine upon purchase. Well written ones told me more or less everything I needed to know on how to play the basics of the game, plus it had cool art and in older ones, hints.
Some notable manuals from days of yore:
Dragon Warrior for the NES. I think that thing was chock full of hints, even if the art in it was kind of crappy (I don't believe we got the Toriyama art here?). Was also in colour, I believe.
Faxanadu - This manual was pretty cool, it had pieces of art in that sort of added to the imagination of the player and what he was doing. For some reason that really sticks out to me.
I never had a SNES/Genesis so I can't comment on those.
Tactics Ogre - the manual was accompanied by a spread that revealed a greater picture once you opened the case. It had the main character fighting off a gryphon that extended to the backside of the front cover. Really cool.
Final Fantasy VII - I loved that manual. Full glossy colours, and screenshots that provided semi-hints.
Baldur's Gate (PC) - This is more like a tome. I bought this game after flipping through the manual, and seeing the level of detail the writers went into to create this world. Sure it had lots of rules and what not, but it was AMAZING.
Much to my chagrin, when I cracked open LR:FFXIII, there was no manual, or at least one that met my expectations as to what an RPG manual should be. I guess I always figured that RPGs would have manuals, because there was always so much emphasis on story that they tended to go hand in hand.
Anyways, any manuals that stand out in your mind over your gaming history?