NetCat
From John Freier
Redirect ports.
This one redirect port 24 to port 22.
24 stream tcp nowait nobody /usr/sbin/tcpd /bin/nc 192.168.1.1 22
This one redirects port 6000(x11) to port 25
x11 stream tcp nowait root /usr/local/bin/nc nc -n -w 3 127.0.0.1 25