ZEG, which stands for "Zero Effort Groupware", is a virtual appliance of SOGo intended to provide a complete out-of-the-box testing environment. SOGo is a collaboration suite (or groupware) with speed and scalability in mind. It offers calendaring, address book management, and a full-featured Webmail client along with resource sharing and permission handling. It also makes use of documented standards (CalDAV, CardDAV and GroupDAV, vCard, and vCalendar/iCalendar) and thereby enables the use of many clients and the reuse of any existing infrastructure. The appliance is prepared to be imported in VirtualBox but can also used in VMWare.
The KiWi core system is a flexible platform for building different kinds of semantic social software applications on top (currently the Semantic Wiki and the TagIT application). It provides all the core services required in such applications, like editing and tagging, the storage of content and associated meta-data, its own triple store, transactions and versioning over content and meta-data, a linked open data server, and many small features semantic social software developers will like (like convenience services for working with ontologies or SKOS thesauruses, etc.).
CGI::ContactForm is a Perl module that generates a contact form for the Web and sends a message to a predestinated recipient. Unlike many form-to-mail programs, it's limited to this single purpose, but it allows you to set up a decently designed form with a minimum of effort. In other words, it's simple to use rather than flexible, even if there are quite a few customization possibilities.
OpenInviter is a script to import contacts (address book data) from email providers like Yandex, Lycos, Rambler.ru, Live / Hotmail, OperaMail, GMX.net, Mail.ru, Mail.com, GMail, Yahoo!, Rediff, AOL, and KataMail. It can import from content management systems like SimpleMachines Forum (SMF), Drupal, Social Engine, Wordpress, PunBB, Joomla, JamRoom, and PhpBB. It also imports from social portals like Twitter, Facebook, Hi5, Friendster, Orkut, Myspace, and LinkedIn. It offers basic "tell a friend" features.
Gutuma is a feature rich PHP newsletter/mailing list management tool that is designed to be easy to install and use. It doesn't require a database, yet offers multiple lists, import and export from CSV, file attachments, drafts, AJAX subscribe gadgets, administrator email notifications, MD5 protected logins, and batched deliveries that can be driven by a cron job.