Howtoforge posted a tutorial about installing Lighttpd with PHP5 and MySQL support on Debian Squeeze
Lighttpd is a secure, fast, standards-compliant web server designed for speed-critical environments. This tutorial shows how you can install Lighttpd on a Debian Squeeze server with PHP5 support (through FastCGI) and MySQL support.Installing Lighttpd With PHP5 And MySQL Support On Debian Squeeze