iptables as WOL packet proxy

sudo iptables -t nat -A PREROUTING -p udp --dport 7 -j DNAT --to-destination <UNUSED_IP>
sudo ip neigh add <UNUSED_IP> lladdr ff:ff:ff:ff:ff:ff nud permanent dev eth0

Download
http://www.depicus.com/wake-on-lan/wake-on-lan-cmd.aspx

wolcmd <mac> <proxy_ip> 255.255.255.255 7