Most folks on LiveJournal belong to a bunch of communities. Some of the good ones are kind of obscure. The "Featured Community" meme encourages people to share their favorite communities.
1. Cite a community that you enjoy.Today's featured community is: specficmarkets
2. Summarize its purpose and parameters.
3. Invite your audience to join the community and/or reply with their favorite communities.
This community offers a place for publishers, editors, writers, and other folks to share news about markets for speculative fiction. Most of the posts are calls for submissions, but there are a few other things that pop up as well. If you are a writer, or in need of writers, this is a good community to check out.