A handy little cron command for Ubuntu is @reboot. For some reason I am too lazy to research properly I kept getting

[psad-status] firewall setup warning

on startup. Not hard to fix, but annoying. So creating a quick script to run

/sbin/iptables -A FORWARD -j LOG
/sbin/iptables -A INPUT -j LOG

and call it from crontab with

@reboot /home/pms/iptables-set.sh

does the trick.