What are "Waponi" and "Nine"?

Hi all.

   Being new, I have noticed many seemingly ongoing projects by numerous
persons on this list.  Some of them interest me and I would want to
contribute.  My biggest problem is that I don't really understand what
these things are.
   The two biggest ones are Waponi and Nine.  These are mentioned all the
time.  But there are other projects being taken up by multiple conlangers,
the names of which I cannot recall.
   If someone could post a brief description of some of these projects I
would greatly appreciate it.  I'm really quite interested in contributing
to the cause.  Thanks so much.

-- Josh :)