Anonymous functions in PHP
I ran into this and found it interesting. Someone has added support for anonymous functions in PHP.
With the patch you can now do stuff like:
$data = array("zoo", "orange", "car", "lemon", "apple");
usort($data, function($a, $b) { return strcmp($a, $b); });
var_dump($data); # data is sorted alphabetically
Before you had to use a funky function generation call.