"Open", "Public", online collaboration service needed for curriculum development. Suggestions?

Hi all,

I am to be part of an NSF-funded program wherein we are developing a model curriculum to integrate math and science in a smallish district K-5. The program director would like the designers to be able to work collaboratively online and to have it open for people outside of us (so, the public) to see readily as the work is evolving.

Ideally it would offer these types of services:
* Discussion boards/locations
* Document storage (and editing would be a huge plus)
* To-Do-Lists
* Project management (timelines and reminders, etc).

We have funding to pay for the service, so it needn't be free.

There are so many many many pieces of this everywhere... I really need some suggestions to help guide our investigations.

Thanks so much for any advice you can offer!

~Brian