Howtoforge posted a tutorial about installing Nginx with PHP5 and MySQL support on Debian Squeeze

Nginx (pronounced "engine x") is a free, open-source, high-performance HTTP server. Nginx is known for its stability, rich feature set, simple configuration, and low resource consumption. This tutorial shows how you can install Nginx on a Debian Squeeze server with PHP5 support (through FastCGI) and MySQL support.

  Installing Nginx With PHP5 And MySQL Support On Debian Squeeze