Try some netcat:
on the host with a writable medium: nc -l 2084 on the host with ro medium: iptables -nL | nc ip.of.host.above 2084 The port can be any old port (above 1024 if you are not root). 2084 is just a Robotron reference.
As an update, here are a few more recipies for nc:
Read about them here:
And in case that blog shuffles off before mine does, this was was of interest to me:
Moving LVM images between machines without ssh On the receiving end do: # nc -l 7000 | dd of=/dev/mapper/vgfoo-lvbar bs=32768 And on the sending end do: # dd if=/dev/mapper/vgbaz-lvquz bs=32768 | nc otherhost 7000