See: Gridcosm - http://sito.org/synergy/gridcosm and HyGrid - ...hygrid
However, we do have narrative graphic projects. For example, we've done a comic book called Impulse Freak, http://sito.org/synergy/ifreak ... There's also an online version of IFreak that was originally developed for HotWired. Modular narrative, but narrative nonetheless.
One project that never really got to a point where I wanted to make it public was called Trangaea, a collaborative storyworld. You can see parts of it at http://sito.org/story
So, yes, we're interested in the written word. Part of that interest is evident in the development of this, the Discussion area. Words are quite important.
What are your ideas for collaborative writing projects?