> Is it possible to write modular kernel device drivers/network
> stacks/filesystems under NetBSD?  If so, are there any good online
> resources?

There are examples under /usr/share/lkm.  There is also an article
on DaemonNews about LKMs in OpenBSD.  The examples don't quite work
on NetBSD:

   http://ezine.daemonnews.org/200109/openbsd-lkm.html

Otherwise, as usual for NetBSD, if you can't find an answer on the web
ask on the mailing list.  Assuming you get an answer it will then be
in the mailing list archives on the web. :-)

Regards,

Giles