While our walk-through for Apache/MySQL/PHP on OpenBSD is quite popular, the upgrade documentation for OpenBSD 5.2 is quoted thus:
nginx (see also nginx(8)) has been added to OpenBSD, ultimately to replace the Apache 1.3 derived httpd(8). For new installations, you are encouraged to utilize nginx rather than httpd, existing installations are encouraged to start planning replacing the stock httpd with nginx.
With Apache 1.3 being awfully long in the tooth, most of us saw something like this coming. With that, there's a new walk-through that covers the basic configuration of nginx, MySQL and php-fpm to create a working, secure and chroot-enabled web application environment in OpenBSD 5.2.
Introducing: The OpenBSD nginx/MySQL/PHP stack