raspberry pi as VPN router

vpnrouter.sh

# Assumes eth0 is WAN and eth1 is the port you want to act as a router for other devices.
sudo apt-get install openvpn
sudo apt-get install dnsmasq

/etc/network/interfaces - add:
#USB NIC serving as internal gateway
iface eth1 inet static
  address 192.168.10.1
  netmask 255.255.255.0

/etc/dnsmasq.dconf - add:
interface=eth1
dhcp-range=eth1,192.168.10.10,192.168.10.200,2h
dhcp-option=3,192.168.10.1 # our router
dhcp-option=6,192.168.10.1 # our DNS Server
dhcp-authoritative # force clients to grab a new IP

echo 1 | sudo tee /proc/sys/net/ipv4/ip_forward

edit: /etc/sysctl.conf
uncomment: net.ipv4.ip_forward=1

sudo reboot

connect to openvpn with:
openvpn --config [myconfig]

Run the following after connecting:
sudo iptables -t nat -A POSTROUTING -o tun0 -j MASQUERADE
sudo iptables -A FORWARD -i eth1 -o tun0 -j ACCEPT
sudo iptables -A FORWARD -i tun0 -o eth1 -m state --state RELATED,ESTABLISHED -j ACCEPT