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topspace=2mm, header=4mm, footer=0mm,
width=77mm, height=166mm]
</texcode>
ConTeXt is also handy when you need to '''rearrange an existing pdf''' into a booklet. This is a trial-and-error solution by Mari for rearranging an A4 pdf file into 2*8 spreads on A3 sheet (-> A6 pages when printed and cut). The texexec.tex file that was created by the first tries with <tt>texexec --pdfarrange</tt> (which didn't seem to have enough options) was a great help while working towards this solution.
Not sure about the margins on the final A6 pages (the original has equal left and right margins, some extra inside margin might be a good thing), but at least otherwise this seems to do the trick:
<texcode>
\setuppapersize[A6][A3] %individual page A6 size, print size A3
\setuparranging[2*8,rotated] %makes an 8 page gathering when folded (duplex printing!)
\setupoutput[pdf]
\setuplayout
[backspace=0pt,
topspace=0pt,
width=middle,
height=middle,
location=middle,
header=0pt,
footer=0pt]
\setuppagenumbering[alternative=doublesided]
\starttext
\insertpages
[original_file.pdf][width=0pt]
\stoptext
</texcode>