You can also use mod_rewrite in apache. I've seen it used to map urls to various ports and services. In addition I believe Apache is coming out with, or has come out with the ability to do load balancing.
Its getting more versatile as a front end to web-services.
Hi Rick, Depends, if you are using only Tomcat to serve all types of pages(static and JSPs) then u need to modify the server.xml
On the other hand, if you are have Apache to serve the static pages and Tomcat to serve the JSPs (Preferred setup) then use either of these : Mod_jk, Mod_jk2, or Mod_proxy and configure them. Once configured you need not point to port 8080 in your URLs.