Having added a number of communities, I've found that my friends page becomes unmanageable. At least once a day, I want to read what my friends have posted. On the other hand, my interest in, for example, sf_* communities is not as great; I read them when I'm at loose ends. I'd like to have this secondary content someplace so I can review new stuff but I don't want to have to sift through all of it to get to the important stuff; my friends.
Lately I've been thinking it would be cool to be able to have an arbitrary number of friends pages; one would be friends, one would be emergency services communities, one would be outright time-waster stuff like sf_* and *macros. That way I could zero in on the stuff that I wanted to look at right now without being distracted or overwhelmed.