Wow, lots of good ideas and info. Keep it coming.
Thanks Cutter for the idea of close npc connections. I had totally forgotten the horror aspect of having to deal with your next door neighbor or favorite innkeeper as a zombie. Or worse, their cute, adorable little kids!
Many people suggested the 'Turn Undead' problem. I've got a plan to deal with that, which I'll explain in a sec in the quick rundown of my Zombi-geddon scenario.
First, I'd really like to incorporate the Tomb of Horrors and it's sequel. I've always liked those and I found a way to have it all make sense. Plus, I get to have both creepy build-up bits AND wake up to full-on zombie horror bits. I'll run them through a few beginning adventures to let them level up and to establish their presence and NPC connections in a quaint, somewhat secluded, island community. They'll return from one adventure (having gained the appropriate level) and have something of interest to one of their friendly contacts out on the island. But the locals on the mainland say they haven't heard from those folks in awhile. The PCs investigate to discover Zombie Island.

All their friends and buddies are now a ravenous horde bent on devouring them. They'll eventually spot a rune covered (semi) uber-zombie that seems the be the source of the contagion. (and yes, I want to have it be a magical disease effect) But before they can kill it, it escapes. I'll try to instill in them a strong desire to track the thing which will lead them into a vast swamp. Along the way the Rune Zombie will infect even more people that the PCs will have to deal with. Eventually they'll make their way into the swamp and find the legendary Tomb of Horrors and the very start of what will one-day be the Black Academy. Hopefully I can get them to actually go into the Tomb (at least the new 3.5 version isn't as deadly as it used to be, AND it's been updated to fit better with the sequel). They'll make it thru the Tomb and I'll make sure they ALL get soul-sucked in the final battle!!

Why kill them all you ask? Because then I get to have the Zombi-pocalypse bit. They get soul-sucked, but somehow are not completely destroyed. Effectively they'll just be Soul Trapped. Lots of time will pass which they are on aware of. They'll have strange visions and dreams and then, in a flash, they'll be freed. I'm not sure if I'll have their bodies reform (as the spell) or if they'll possess new bodies (low level acolytes at the academy)- whichever, they'll find themselves in the middle of the Black Academy
after Acererak's has
succeeded with his apotheosis!! The lich has become the embodiment of undeath and the 'black intrusion' of the sequel has infected the world. (including it's making things more resistant to turning!) Anyone who dies, or was dead, has risen again into some form of undeath! (so I also get to have lots of different types of zombies- slow, fast, wall climbing, reforming from hacked of bits, still attacking even while hacked to bits, etc.)
The PCs will have to find a way out of the academy and survive long enough to discover the few remaining strongholds of the living. Eventually they'll discover that while Acererak was successful in his plan, he is still bound to his phylactery (and more importantly, he is not aware of this weakness) If they can destroy his phylactery, they'll undo all his evil works and all the lifeforce that he's stolen thru the ages will be returned. (a cure!) So they'll have to go back into the Tomb (which will be amped back up to 1st edition deadliness
![Devious :] :]](http://www.enworld.org/forum/images/smilies/devious.png)
) and beyond, thru the City That Waits and to the Fortress of Conclusion.
All told, it should be a campaign worthy epic. What do you all think?