1. Go to Knowledge Base tab
2. Click Add Bulletin Board
3. Fill in the data in Bulletin Information tab
4. Go to Permissions tab
5. Click Add New Permissions
6. In the Permission Type drop-down list select Group and pick All Users group
7. Set "Can view this article' and "Can view article entry" to Allow.
8. Click Add and then Save Bulletin Board
After that when any member from All Users group logs in, he will see the Bulletin Board entries scrolling in his Home page.