A moment of
insight, often profound, sometimes (depressingly) fleeting. A point where a person's understanding of whatever it is that they're trying to understand, goes transcendental and the complete picture is revealed. All of the disparate entities fall into place, and are meaningfully connected (hmm, much like Everything?).
Gestalt flashes (in my experience) occur a lot when studying math-related things like
calculus,
physics and
computer science.