Everyone that knows of the social news site Digg.com knows the problems that being linked on it can cause. Smaller servers get overloaded and pages can either be very slow loading or completely offline within minutes of being "digged". There's a few out there that have come up with different solutions, but several of them involve mirroring the content somewhere else. In this proposal, however, they combine the power of Lightttpd and PHP to handle the loads.
We host a wide variety of sites, covering everything from converting your garage into a living space to video game addictions. Because we are such a small operation, being hit by a link from a big site such as Digg would be both a blessing and a curse.
In order to place our ads on each page, we use PHP's auto_append_file feature to run our advertisement code. By using PHP's other neato function, auto_prepend_file, I can create a small piece of PHP code to detect when the site is being hit by Digg. In this situation, I have chosen to use Lighttpd to handle the increased loads, because of its proven high performance with large numbers of concurrent connections.
In his example code, he shows how you can detect when a user is coming from a digg.com page and take them to a cached version of the page they've requested (with the .cache extension).