I had a crazy dream last night, where it was kind of like a L4D campaign. (Not making this up)
Well, needless to say, it was badass, and I remember a great deal, and even have maps and scenarios drawn out. (Bored in Sociology.)
It started out something like this:
We started in a giant power substation on top of one of the larger box-like units.
(Think the one in the picture, but nothing coming out of the top. And at night.)

The place was huuuuuuuuge (leik xbawx), and there were not a whole ton of zombies (just kind of eerily quiet), which changed a bit near the end. No molotovs, no pipebombs, etc. Just creepy openness. Towards the back of the place, was a giant building, like a mill or some kind of run down factory. There was a cargo container (a la HL2) with the bottom open leaning up towards a window. Climbed up the inside, and in to the window.
So inside the window:
Ended up in a stairwell, one way was blocked, the other way went down. Climbed over the debris, and walked up to a open door way. Corridor with rooms on the sides that ended up looking like this
[]| |[]
[]| |[]
Us
So there was a creepy old tv that was on with a broken down office chair in front of it, so we were all sneaking and shit. (Think of a bioshock-y ambiance.) Found some ammo in the side rooms and when we walked past the forward most rooms, we came to this huge room with a catwalk across.
That's all I remember as far as the place. There was this old dude in a tux and tophat (Think Wild Wild West Steampunk ish) at the other side of the walkway with a giant revolver, and he gave us guns and stuff.
So anyways, I kind of have all of this drawn out, and I think it could make for a cool campaign. I might start working on it as a side project, just because it was a really vivid dream and I want to see if I could almost bring it to life.
Yeah. I'm not crazy. I swear.
Also:
tl;dr - I had a dream with a bad ass map idea.