From mid 2007 to mid 2010 I helped to develop the concrete5 content management system, joining them at OSCON 2008 for the open-source release through the 5.4 release at SXSW 2010. I've since moved onto a development position with MusiciansFriend.com / Guitar Center, but continue to develop and support my own collection of concrete5 packages, and try help out in the forum when I find the time.
You can check out my concrete5 blocks & applications here:
http://concrete5packages.com/toolbox/
Or if you're looking for some help with things, here's some of my background:
http://portfolio.inneroptics.net
...and I'm on twitter here: http://twitter.com/tonytrupp/