Ok, guess it's up to me to start then… 

I've been working with Reiki for some time now with the understanding that it is a subset of Qi Gong; this is a product of research which has shown that many of the techniques used by the eastern tradition of Usui Reiki Ryoho come from the practice of Ki Kou, a Japanese form of Qi Gong.  Much of the mythology that has built up around Reiki in the West was never part of the original Usui system, and much that was part of Usui's work has been forgotten by the Western branches of Reiki though some systems have attempted to replace this lost material with information from other systems and traditions.

Because of this understanding, I've looked more into other systems that work with vital energy, and fused information from those systems with my practice of Reiki.  Huna, a system of hawaiian-themed shamanism heavily influenced by theosophy, has been one very useful source of information.  Its view of mana, in particular, provided a framework by which to understand the “apparently sentient” behavior of Reiki as described by Western practitioners.  From The Secret Science at Work, by Max Freedom Long:

The most interesting thing about mana is that it seems alive and seems to have a form of intelligence of its own. This is not really so. It can act only when it charges and vitalizes aka subtstance, as in an aka finger which is projected, and the consciousness is invariably that of the low self who is dictating the projection and also the things it is to do.

Looking into the Huna concept of the low self further provided an understanding as to why Western Reiki has been aptly described as “intelligent, but not brilliant” and why an intelligent system supposedly oriented towards healing can make basic errors such as driving a fever up dangerously high (accelerating the body's own mechanism to burn out some forms of illness.)

Another very useful discovery came from the work of Franz Bardon, in the form of the “fluid condenser”, based loosely around Mesmer's concept of a magnetic Fluid and correlated with information from other magical/occult systems as well as the Odic work of Baron von Reichenbach.  A fluid condenser in this context is a tool used to accumulate and concentrate these energies, and is very similar in many respects (including ingredients) to a modern orgonite-based orgone accumulator.  Combined with Reiki/QiGong techniques, this could provide quite a boost to many workings, particularly if further coupled with magical tools/technology such as the Crystal Grids or Orgone Crystal Matrix.  I'm still working on fully grasping the Bardon material, and incorporating it with my understanding of the other systems.