Productivity/Information Tool support

About a year and a half ago I heard about a product called Near-Time Flow. It's a publishing and collaboration tool, that can be used for researching, gathering information, searching, organizing and more. The problem for me is that it's a OSX program. And I don't use that.

But now the question. What programs are there for linux that can do this, or part of it?

One thing that comes to mind is the scrapbook extension for Firefox. This can be used to research webpages. But Flow does a lot more, some of which is really useful like version control and collaboration. Here I think of subversion, which can help with that.

Are there other programs that help to organize information? Maybe evolution, but that's very specific for PIM stuff. Maybe some kind of wiki, can be used, but then you will miss the special functionality that's so useful.

I'm not really sure where this is going. These are just ideas and stuff.

Another link with ideas about this is on 43folders: I want a pony.