I felt what I would call the holy spirit not long after I became a chrisitan.
It felt like turning on a heater and getting warm but instead of heat, the being radiated love! if that makes sense? It was a definite prescence and the person I was praying with, while they didn't feel the spririt - did sense that something was going on.
I've also felt a few times what I called a demon, sitting on my chest, but that was usually under the influence of cough medicine so may not actually have been metaphysical but more night time paralysis!! Still, that doesn't invalidate the experience however it happened? Perhpas medication/drugs/meditation opens us up to things our "rational" brain dismisses otherwise?