Something Wicked this Way Hums by
like_a_raven Not only a freakin' brilliant title in the "how I wish I'd thought of that" level of freakin' brilliance, but a Glee/Supernatural cross that works. Timelines slightly adjusted to put teenage Dean in Lima, Ohio at the right time and written more in the Glee style, these are still very much the Winchesters (John circa S2 before Kripke's daddy issues got overwhelming) and Dean's internal voice is priceless.
It probably works better if you know both shows but I suspect familiarity with one and a passing knowledge of the other would work almost as well, it's just that good.
Four parts. All posted.