Benzene's ring structure was discovered in 1864 by German chemist Friedrich August Kekule. He was inspired by a dream he had, in which he envisioned organic molecules as snakes, and he saw one of the snakes biting its own tail. In his own words, from a speech he gave twenty-five years later:
During my stay in Ghent, I lived in elegant bachelor quarters in the main thoroughfare. My study, however, faced a narrow side-alley and no daylight penetrated it ... I was sitting writing on my textbook, but the work did not progress; my thoughts were elsewhere. I turned my chair to the fire and dozed. Again the atoms were gamboling before my eyes. This time the smaller groups kept modestly in the background.
My mental eye, rendered more acute by the repeated visions of the kind, could now distinguish larger structures of manifold conformation; long rows sometimes more closely fitted together all twining and twisting in snake-like motion. But look! What was that? One of the snakes had seized hold of its own tail, and the form whirled mockingly before my eyes. As if by a flash of lightning I awoke; and this time also I spent the rest of the night in working out the consequences of the hypothesis.
He published his paper concerning benzene's structure less than a year later to the Chemical Society of Paris, solving a problem that had concerned modern chemistry for years. His findings weren't only of great theoretical importance, but were useful in the dye industry of the time, and Kekule was offered an appointment to the University of Munich based on them alone.
Never stop dreaming.