If pound is not good enough, there are many other programs to be found via
Freshmeat [freshmeat.net].
I don't agree on the 'related' tasks. Load balancing and webservering are not related, I think. A load balancing server should only run load balancing software, no webserving software. A webserver server should only run webserving software, not load balancing software. And load balancing at TCP/IP level is totally different from handling HTTP requests.