Post the 5th line on the 13th page of your current book...

[xNuclearWonderlandx]

"Finally two salesmen brandishing tire irons came to the door and we managed to negotiate the sale through a tiny slit."

[Magician Arcana]

Bran titled his head, and she saw his eyes shift, just a little, gleaming gold in the dimness of the outer hall.

[Manga N Anime girl]

"...sounding superfeminine and ultracheerful. It's less like..."

[flayeflaye]

He drew the stones closer as if to protect it from Sloan's wrath.

[Vale-Vane]

...in darkness without end which he will never return. If you don't care....

[Gallendro]

It was just then that Mr. Jones woke up. The next moment

I'll give you a hint: Oink oink

[Rainbow Batty]

This is something I was never able to do before; I have never identified with my female classmates, peers, and certainly not with media representations of what a female is and should be.

[Ysavvryl]

Hush! Caution! Echoland!

(lol...)

[la balena]

twisted, actually writing something! making letters in the sky! Every one

[blackheartgirl2]

the book i am reading is at school but this is one of my favorite books.

"... word for it."

haha that is so not helpful at all.

[Manga N Anime girl]

The page marked 13, "...been to Australia and was really up to Tokyo; Alice, who..."
Actual 13th page, "Adam grabbed the paper. 'Where?'"

[Infinity Outlaw]

The world is not beautiful

"...forbidden, but the novice was curious at least to learn..."

Therefore it is.

[pi rho maniac]

Page labeled 13:
"...between his Python work on TV, stage, and in film, as well as co-..."

13th page (which, with all the forewords/prologue, ends up being page 7):
"...may well have been the other Humphrey, Lyttelton. 'The Barclays arrived with..."

The second one probably gives it away more than the first, I think.