Niall Kennedy - Rasmus Lerdorf on scaling web apps with PHP:

"Rasmus Lerdorf led OSCON attendees through a series of optimizations for modern web applications using PHP at O'Reilly's Open Source conference today. Most programmers use default installations and configurations for their web applications and never really dig deep within their stack or their own code to optimize page load and latency. The full slides from Rasmus's talk are available online and I recorded audio of the entire session from the front row."