Well my trusty old Canon BJC-4000 finally died - given that it only cost five pounds from a jumble sale I can't complain. Setting it up was easy too, as described over on the Slackware page.
But now I have a Samsung ML-1640 mono laser printer and that was much more "fun". It is advertised on LinuxPrinting.org as working perfectly with the drivers as supplied by Samsung. I tried this every which way - but no joy. It seems that they have packaged the driver badly - vital libraries cannot be found even when they exist and are in the right place. And because the Samsung driver is closed source, one is stuck - no good trying to download the source code and re-build from there.
Ports to the rescue! Splix is a set of open-source drivers for SPL (Samsung Printer Language) printers, and is available in ports. So ...
cd /usr/ports/print/splix
make install clean
/usr/local/etc/rc.d/cupsd restart
Then set up cups as usual.
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