While OACS is obviously for the web, I don't think "web" conveys
anything particularly distinctive about the project. Everything is for
the web these days. "Com-Unite" is cute but a little too Karl Marx
for my taste.
If "collab" weren't already so overdone, I'd suggest using it as
part of the title. I do like "Open" and would prefer to keep it as part
of the name, if possible.