[UPDATE – May 23rd ’14]
I have included an update to this article which features new code and a downloadable plugin. Please note that this post simply shows a method I use to implement featured images into projects I am working on. If you attempt to use this method in your projects you could run into unforeseen issues. This is especially true if you are not familiar with developing in PHP or WordPress. I don’t recommend trying to implement this into your theme as such as it is not simply obtained by copy and paste. This article simply shows a method I use.