This one was actually a recurring nightmare.

The sound of tortured screams can be heard in many directions for varying distances, but all in serious pain. Eyes open to the scene of a large room. At second glance it's actually more of a jail cell. I'm inside a hanging cage in about the center of the room. Below the cage is quite the pit of lava (magma? don't know if I'm underground or not). I'm a little more focused now and take note that there are windows around the pit, but they don't seem to follow any pattern. I try to focus on one window, to see if I can see anything beyond it, when a resounding BOOM shakes my surroundings. The booms continue in the pattern of footsteps, but definitely something very big. Suddenly text and warnings start to scroll across my glasses (no matrix jokes, this was way before that movie). The booming stops and my cage jolts in one direction. Shaken, I look up to see a fiery pair of eyes. The world starts to fall upward and a warmth builds behind me. Just how long is the eternity between realization and eternity... darkness...

Here's a more recent one, it's kinda fuzzy in my head though.

It's cold. I have to keep movie for them. Family is the only thing that keeps me leading them North. My Mother, Aunt, and I are in a snow covered woods somewhere close to the USA/Canada border. The hordes aren't too far behind us. We come over a ridge to find a well fortified farm populated by a good number of people. Time jumps while we're here, but I know we had at least a moment's hope that this place could be the refuge we prayed for. No such luck. Not a week after our arrival, the echos of moans and shuffling can be heard coming along the same trail we took. Everyone springs into action, grabbing what weapons we have. My Mother goes to secure escape routes while my Aunt mans a mounted turret set up in the doorway of the barn. I'm handed a shotgun and as always have my sword strapped to my back. The fences hardly even slow the undead down. As with all battles, details become blurred. I remember that we were overrun. I'm bitten on the arm trying to knock back the flood. I'm given a moment of clarity to look back at the other survivors. We all know I'm a lost one now... but, that wasn't the time for tears. I nod to my Aunt and she understands it's time to run. She gives one last volley from the turret to clear the newest wave in front of me. The humans run... I draw my sword... This is both the greatest and worst moment of this miserable existence. A single tear runs down my cheek as I let out a feral roar and charge the sea of cursed souls. I'm not all that eager to join them, so I make sure they get a large helping of steel before they get another taste of me. My last view is of a warrior standing atop a mountain of decay, veins blackened, eyes white, defying the curse that claimed so many.

That is a nightmare to me. Zombies are a real fear of mine O.o Other than a microscopic threat, what could be worse then the dead raising to devour the living?

Please, point others to this TheO "World", I can't be the only one who remembers these flashes of other worlds (he means nightmares, Brian's just really into that writing style at the moment... crazy person).