I posted to pingomatic using curl with code like this
$curl = curl_init($this->buildURL());
curl_exec($curl);
But got the reply
You are too awesome for Ping-o-matic
Why am I too awesome for Ping-o-matic?
EDIT
I am posting to pingomatic but not POSTing to pingomatic. Their setup just takes a simple GET request
Pingomatic requires the user agent header be set. Adding this fixes the problem:
The code would then look like
Source: http://www.krunk4ever.com/blog/2011/12/21/you-are-too-awesome-for-ping-o-matic/
Github project: https://github.com/DynamiX-Web-Design/DxPingomatic