Cult-foo

WordPress has grown to 2.5.1 version and almost all old bugs were fixed. But a lot of wordpress users still lacks tree-like comments structure, like in LiveJournal, in which tree-like comments - habitual and convenient thing. But WP kernel doesnt contain function of building tree-like comments.

Plugins, which implement threaded comments:

1. Alex’s Threaded Comments
   
2. Wordpress Thread Comment
   
3. Disqus
   
4. Intense Debate
   

If you know more similar plug-ins for WP, post them in comments and i add them to the list.