Hi all,
So I'm running the tech side of a high school Model United Nations conference, one of the largest in the US. We have about 2500 delegates and 170+ college students as staff, with dozens of committees, several computer labs, etc. The conference runs for four days, during which time delegates collaboratively write resolutions, present them, amend them, etc. Currently this is done with a plethora of flash drives carrying Word docs, and last year it was confusion. Our directors have asked us if there's something we can set up to perform a certain number of functions:
-Check attendance at the conference sessions
-Upload documents

My mind immediately went to the wiki concept, which does more than the original idea, but sounds quite reasonable. I'm imagining a (preferably hosted) wiki where delegates set up their own accounts, visit committee websites, upload their resolutions, edit the resolutions in large groups, and submit them. We can also post documents as committee staff, and people can do attendance by appending their own signature to an electronic document. So my requirements would be:

-Large user base (2700 or so)
-Permissions and protection, to safeguard the central pages from malicious or accidental vandalism
-Hosted, so we don't have to set up a physical server in the hotel at short notice.
-WYSIWYG editing, for non-technical students
-Ability to partition wiki into subgroups so each committee can have its own folder/page/etc.

So my question is: can you think of a wiki which would do this? We have the money to pay for a solution, if needed. Or should I stick to the simple concept of a Google Group to upload documents, and have minimal collaborative editing? I'm open to any sorts of suggestions. I'm leery of relying completely on internet access, however, especially since we've had connection problems in the past.

Thanks!

-Owen