I recently watched an Anime series which had as a central theme a building known as the Infinite Castle.basically a whole heap of developers tried to make a massive building, but the economy fell and the development was left unfinished. Squatters and gangs moved into the building, turning it into a vertical barrens.
This sparked the idea for an alternate SR timeline. Imagine if Renraku had not fared so well in the Corporate War and could not afford to reclaim its arcology, due to the repairs needed to be done. No other Corp can be bothered touching it, and no one can afford to remove such a large structure. With all this free space right in the middle of downtown, alot of orks and so forth migrate to it from the underground. Lonestar and Renraku comes under pressure from the rest of the corpotations to do something about it, as they don't like a massive crimne infested slum that close to their pristine buildings. In responce, Renraku and Lonestar simply baracade the place up and put a wall around it, policing who goes in and out. People can still coem and go via the underground, which starts to make quite a bit from the "underground railway" that has access to the building. Many low wage workers who sweep the floors and mop the toilets of the Downtown skyrakers decide its work the risk living in the building as the rent is almost free (Except for taxes to the gangs) and they are very near work.
All this fits in okay, except for a few minor things. Firstly, it requires alot of power so someone would have to have control of the reactors and maintain them. I figure someone may have bought them from Renraku in order to make money off selling the power to seattle and the new residents of the Arcology. The other things were sanitation food and so forth, but I figure they would be handled much like they are in the barrens. In order to get a big influx of people I thought this could coincide with the "reclaimation" of Redmond, which would frce out alot of the poor and sinless.
Thoughts and Comments welcome.