If tunnel machine is router:

tunnel machine:
ssh -g username@ssh.es.aau.dk -nNfL 1234:ordbogen.com:80
iptables -t nat -A OUTPUT -m tcp -p tcp -d ordbogen.com -j REDIRECT --to-port 1234
iptables -t nat -A PREROUTING -m tcp -p tcp -d ordbogen.com -j REDIRECT --to-port 1234

client:
nothing :)


If tunnel machine is NOT router:

tunnel machine:
ssh -g username@ssh.es.aau.dk -nNfL 1234:ordbogen.com:80
iptables -t nat -A OUTPUT -m tcp -p tcp -d ordbogen.com -j REDIRECT --to-port 1234

client:
sudo iptables -t nat -A OUTPUT -m tcp -p tcp -d ordbogen.com -j DNAT --to-destination TUNNEL_MACHINE_IP:1234