Basically I need a hosted solution, where one can create an account for a project and the distributed team members can interact through that site during the project implementation. I know a lot of such software but not a hosted one.
I think Basecamp is the most popular one.
I'm trying the CodeSpaces now. Looks promising.
I use codeplex.com from Microsoft and find it excellent, it now accepts svn connections as well as Team System.
An excellent alternative would be code.google.com, which I've not found wanting.
I would propose that both of these are very popular and of the highest quality and many will have opinions on which better suits your needs. I can't give a narrower answer without knowing more of your particular needs and preferences.
I think that VersionOne offers both hosted and onsite web based versions of their tools. The Team Edition is also free for a limited time. Rally Software offers basically the same deal (hosted and onsite) versions of its software. Again, the community edition is free.
来源：https://stackoverflow.com/questions/236091/what-online-collaboration-sites-do-you-know