Hep Message Server is software that transfers messages between different messaging systems. Eventually, it should transparently route messages between email, weblogs, and instant messaging. Currently Hep does one thing: fetches news feeds from Web sites and lets you view them in your email client.
C2::Newsletter is a simple tool for sending newsletters to your visitors. It allows you to create multiple newsletters, so your visitors can select which topics they want to receive. There is an admin interface to add/edit newsletters and recipients, and send in plain text or MIME-encoded. It is easy to use, but currently only in German (English will be available soon).
Collaba is a multimedia collaboration and communication server built to provide digital workspaces to virtual educational, corporate, and other communities. It features secure email (Web, POP3/SMTP, crypto, and anti-spam), online forums (Web, RSS, NNTP, and podcast), blogs (Web, RSS, podcast), multimedia chat (text, multimedia panel, etc.), personal and group calendering, address books, bookmarks, an online Web page editor, file services and CMS (Web, WebDAV, FTP, SMB, CIFS, anvi-virus API, and ClamAV support), digital portfolio, dynamic news board, directory access, support for multiple independent communities on one server, Single-Sign-On features (built-in support for LDAP, CAS 2.0, JAAS, SMTP-Auth and more, powerful developer API), full online server management, anti-spam (RBL and filters), anti-virus support, centralized management with LDAP directories, Web publishing of personal, group or general web sites, developer APIs, and much more.