PHP __get weirdness

chains.php

<?php

// You can do some very odd things with PHP's __get method

class Chain {

    private $chain = array();

    public static function it() {
        return new self;
    }

    public function __get($property) {
        $this->chain[] = $property;
        return $this;
    }

    public function __toString() {
        return join(" ", $this->chain);
    }
}

echo Chain::it()->Building->up->a->chain->oh->yeah;

// prints "Building up a chain oh yeah"