I do internal gongfu, it's aan easy label for a group of styles that tend to micromanage power generation and motion in similar ways to styles often termed internal-external or external-internal.
That said, I don't think it's something to use to exoticize the style, merely the common term used to define what you train. No chi balls, and no claim that boxers and muay thai guys and other people don't use many of the same ideas in their own ways.
That said, I laugh my ass off at guys who do "external" kung fu and talk about how internal guys are the reason people think kung fu isn't good for fighting. First, most people don't realize taiji is kung fu, they think they're two different things. And second, external kung fu guys probably represent less in fighting comps than hsing yi, Chen style, the Hakka arts, and the other styles often refered to as internal or internal-external.
I also enjoy using the term to make people who worry too much about semantics cry.
In all honesty, most of my training time is working throw setups in a resisting fashion, drilling strikes, and the same things everyone else is doing. I study shuai jiao and judo books galore to crib the notes of others on similar throws to what I'm training, I have a number of boxing manuals that I read and crib notes from for strikes similar to what I'm doing, etc. Nothing exotic, but if it helps, I do retain jing, but mostly because I like being *****.
Since you asked.
Originally Posted by Scott R. Brown
). It postulates that internal actually refers to styles created inside of China, specifically those of Daoist origins, while external refers to styles with origins that have been imported such as Buddhist or Muslim roots. 
