Yes. No. There's Jabber.
Yes, z was down.
No, the mailing list is still up. The link at the top of the page points [link|http://lists.warhead.org.uk/mailman/listinfo/iwe|here].
There's also [link|http://z.iwethey.org/forums/render/content/show?contentid=193926|the Jabber server that Peter set up]. It's not trivial to get going, but it's not too difficult. A couple of recommended clients are [link|http://z.iwethey.org/forums/render/content/show?contentid=156269|here]. I'm using Exodus.
HTH.
Cheers,
Scott.
