While CodeIgniter provides a disk caching mechanism, it lacks a browser caching mechanism. Without a lengthy introduction, here's one.
Browsercache.php: A simple browser-cache-handling library for CodeIgniter
Fix CodeIgniter IP address detection on lighttpd
If the results of a call to $this->input->ip_address() gives you "0.0.0.0" (the "invalid address" response) and you're running lighttpd as your web server, you may be able to fix it with a minor tweak to by …