Self written, no framework used. It's a simple blog with quite custom requirements so I figured whynot just build a custom one. It runs on an Intel Atom, 1GB RAM (and there's more to run than a wamp stack). and 832kbps uplink.

As for software, I wrote it for PHP 5.3 (nowadays upgraded to 5.4 though) with MySQL and persistent database connections. The server is Windows 7 with apache 2.4.