Breaking the LAMP loop, alternative web serving methods

Lately I decided to look elsewhere than the usual "linux apache mysql php". Reading on docs makes me draw something like apache or ngingx as a load balancer front-end, the same as the backend adding lighttpd for fast streaming ofdata. This leave me more confused than before:

I thought myself using a beast like apache to do load balancing was a bit like killing a fly with a nuke, so for I looked elsewhere for two solutions, reverse proxy or tcp-loadbalance? and then apt-cache search came to the rescue:

Reverse proxy, load balancer and HTTPS front-end for Web servers

Yet Another Web Server(in erlang)