For those who did their computing education some time during the dark ages and where some of the more interesting recent concepts such as dependancy injection are new, I found this article at CodeProject (it is based on Spring.Net, but the content may be useful to some).
Dependency Injection Frameworks - Part 1 - Introduction
By Ashish Kaila
http://www.codeproject.com/KB/architecture/DependencyInjection-1.aspx
Enjoy (or not as the case may be)