On his blog today, Zak Greant points out the talk that Rasmus Lerdorf has given at this year's OSCON - "How to Make Money with PHP", complete with a link to slides.
Rasmus is presenting his "How to Make Money with PHP" session for the Portland PHP User group, OSCON attendees and OSCAMP attendees. This session is one of my favorite Rasmus talks - the concepts that he teaches are key to helping PHP developers move from being frustrated novices to being happy and productive PHP hackers.
Some of the key things that the session covers are how to find bottlenecks in your PHP application, how to plan for capacity and (of course) how to make huge amounts of money with PHP.
As mentioned, here's the link for the slides. It looses a bit when it's not being presented right there in front of you, but the 23 slides provide more than enough information to keep one busy for a while.