Just spotted a laminate flooring cutter in a local discount store ad.
<
http://www.hofer.at/at/media/offers/01_10kw36_do/kw36_do_14_d.jpg>
This should work for PCBs, it's the same principle as a sheetmetal
nibbler, just on a large scale.
Since it cuts out a narrow strip, individual boards would have to be
separated by a gap, but it should not tend to run to one side like
other shears since everything is symmetrical.
30eur is a bit much just to try it, but I'm sure that type of cutter
is available elsewhere and maybe someone wants to try it...
ST