On the Box UK Labs site there's an interesting dependency injection tool that uses Reflection to get some of the work done.

Dependency injection is a well known concept, and there are currently a plethora of DI containers available from one of the interweb's many pipes. These include Symfony and Crafty, while the Zend Framework also has its own DI container. So why another? One of my personal goals as a developer is to make things so simple, even I can understand them. But most of the DI containers I've come across require too much configuration, and usually via XML - yuck! So how is ours different?

The tool, boxuk-di, makes use of the Addendum tool to create injectable objects easily accessed via a namespace. You can also use type hinting, scoping and annotations to do special things (like make singleton injection objects). The also mention how primitives are used as well as dispelling some of the misconceptions around reflection and this particular tool.