There is a ULP for eagle to "panelize" a board (put multiple copies of a
single PCB layout into one gerber/etc output, without the parts on each copy
be renumbered.)  As far as I know, it works by copying everything that would
have been on the silkscreen to a new layer and "freezing" them there.  The
actual part numbers change, but since the layer you're actually USING for
the silk screen is "frozen", it doesn't matter.

I would think it would be pretty easy to use a similar technique to allow
multiple boards to be combined into one...

BillW

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