[Hanselda]

Many pdf files come for the printing, thus usually some large margins. But to read on Cybook you don't want margin, or do you? For me I just want as much space to display the text as possible.

I found one tool under linux. Very simple:

PDFCROP 1.5, 2004/06/24 - Copyright (c) 2002, 2004 by Heiko Oberdiek.
Syntax: pdfcrop [options] <input[.pdf]> [output file]
Function: Margins are calculated and removed for each page in the file.
Options: (defaults)
--help print usage
--(no)verbose verbose printing (false)
--(no)debug debug informations (false)
--gscmd <name> call of ghostscript (gs)
--pdftexcmd <name> call of pdfTeX (pdftex)
--margins "<left> <top> <right> <bottom>" (0 0 0 0)
add extra margins, unit is bp. If only one number is
given, then it is used for all margins, in the case
of two numbers they are also used for right and bottom.
--(no)clip clipping support, if margins are set (false)
--(no)hires using `%%HiResBoundingBox' (false)
instead of `%%BoundingBox'
--papersize <foo> parameter for gs's -sPAPERSIZE=<foo>,
use only with older gs versions <7.32 ()
Examples:
pdfcrop --margins 10 input.pdf output.pdf
pdfcrop --margins '5 10 5 20' --clip input.pdf output.pdf

For me it comes with tetex. I think it is also in TexLive or similar. This program will call ghostscript to do the formating. It works but very very slow. So be patient.