Apache
Documentation
http://httpd.apache.org/docs/2.3/mod/core.html
proxy
The idea is to receive all incoming requests on a single HTTP server. This server, using mod_proxy and mod_rewrite, will route requests to X backend servers, acting as a reverse proxy. This can be done very simply once mod_proxy is installed, by adding lines such as:
RewriteEngine on RewriteRule ^t(.*)$ http://somewhere.com/ [P,L]
This would route all requests starting with a t to the site somewhere.com and present its contents to the user as if delivered by the front server.