I'm unsure where the best forum to post this in since it covers a few series, but I figured I'd take a stab here.
In the Voyager episode, "Deathwish", Quinn (formally Q) tells Tuvok that the Q have weaknesses and only appear to be omnipotent because they possess technology that greatly surpasses the technology of the Federation in the 24th century.
It got me wondering: What is the true face of the Q? What makes them so powerful.
I got to thinking that if Qs are so potentially weak, it got me wondering if maybe perhaps their true form was something similar to the species we encountered in the TOS episode "Return to Tomorrow
". To me it would make sense if the Q have either become disembodied or choose to keep their real bodies in such a place (known to us perhaps as the Q continuum) while tapping into a source that allows them to navigate the world exclusively as the essence of their mind and that most of their tricks are some sort of super advanced version of holograms.
I find myself wondering if this explanation might explain a lot.
I don't think anything in this potential explanation is invalidated by any material. If anything, I think "Q&A" still seems to support it.