Libcurl Error Codes
Just a very brief look at speeding up form submission by delegating the processing and bandwidth to your server, not your client.
Part II: Example illustrating how to speed up GET/POST form submissions. Uses fsockopen to initiate a server-side background request to process the submitted data, so that the result page of the form is displayed to the client lightningly quick.
A WordPress plugin that caches your entire blog for WP-Cache, I love this plugin and finally released it to the public!