Fantasy and medieval stuff... Problem is, a lot of people have been selling things just because it's fantasy, they can make any crap they want so sometimes it's hard to find the good stuff, like LOTR and Harry Potter.
The only time I'll read history books is if they're interesting (I have never yet found a good history book besides Horrible Histories, The Very Bloody History of Britain, and this one thing called What Life was Like Among Druids and High Kings). Most history books are horribly boring and only make up for it in pictures.
But I love those little teensy books for kids about new pets, specifically cats, dogs, gerbils, hampsters and horses, the first four of which I have experience with. They say things like "don't pull Kitty's tail", but I just want to write in the consequences, like "Or Kitty will take her claws to the hand pulling her tail and you will have a bleeding stump of a clawed wrist where your hand once was".
Dogs: "You can take your dog on nice, long walks as you both enjoy a slow stroll through the park." My addition: "Unless your dog is a Siberian Husky or other sled-pulling dog, in which case you'll take him on long, painful walks which involve dragging across the asphalt until you bleed enough to attract a mountain lion..."
Gerbils: "When you get your gerbil trained up, he'll be sociable, friendly and nice." My addition: "Before he's trained, he'll be an absolute nightmare and bite all your fingers off."
Hampsters: "When you first take him home, make sure he has a clean cage." My addition: "Because you want him to be happy, as he'll die in three weeks very suddenly."
Horses: "Approach a horse slowly, as horses are easily spooked." My addition: "Especially by Nazgul."