Here is another dependency framework to add to the list: PHP-DI
It is a container meant to be very practical to use, following convention over configuration (so you end up writing much less configuration than with other containers).
It features dependency injection through annotations (which is optional) and minimal configuration:
class Foo {
/**
* @Inject
* @var Bar
*/
private $bar;
public function hello() {
return $this->bar->sayHello();
}
}
Be aware that annotations are optional though, if you don't like it you don't have to use it.
It's very easy to use, and it integrates with Zend Framework and Symfony very well.
(disclaimer: I do work on this framework)