Create a new forum for free and feature with adding Adsense.

 I create a forum:
http://jiansen.do-goo.net/computer-music-and-job-searching-f2/
Everybody can post via clicking NEWTOPIC, but members
can chat online, modify and delete their posts when they login.
do-goo.net  is very good for  creating a free forum.
I also can insert Adsense in the sidebar of the forum. In principal, forum should have more visitors than Blogs in long term.