LAN Port forwarding with a dynamic IP address

[Zac Hansen]

I have a single, dynamic IP address. I have multiple boxes behind a linux
router, one of which runs a web server on port 80. I have set up rules (a
PREROUTING and a FORWARD rule) to let people outside my LAN deal see my web
server. The problem is that the boxes on my LAN can't see them.

I really don't want to hardcode my external IP address into any rules and I
don't want to do any DNS work to make the LAN boxes look up the actual
server's LAN IP address directly.

Can I get my LAN boxes to see my web site and not do the things I don't want
to do?

Thanks.

--Zac