A secure member's only blog purpose-built for a group I participated in a while back.  This site is slightly unique in that there is no public side of the web site.  The only publicly visible page is the login page.  Once a member successfully logs in, an active forum and fairly lively discussion group opens up, but because the site is totally private, you are free to discuss what ever you'd like.  This was built to be a sorta live group discussion, group blog, and public group support & collaboration site . Also features the ability to e-mail an individual or the entire group with a single mouse-click. A group-wide calendar rounds out the main features.