Reverse http proxy using CentOS6 (or Fedora)

[Basher52]

My ISP sent me a mail a couple of days ago telling me that we're about to lose our 10 public IPV4 addresses and that you only gonna have one left.
I need to setup a gateway for all computers but I have 2 web servers each on its own public IP address and I need to be able to use those after this is done.
I know I can't use port forwarding in iptables to redirect port 80 to two different servers so I need something else.

I've found something called reverse http proxy but I can't seem to understand it or even set a small test project up.
Am I correct that if I can set this proxy up the web servers need no special reconfiguration at all and that the servers will still be public as in anyone can get into to them using their original URL?

and if anyone feels like it, a link or howto would be really appreciated.

[Basher52]