The Taridium ipbx is a complete software-based VoIP PBX system that replaces a traditional proprietary hardware PBX. It runs on Linux without the need for extra software licenses, and is based on the SIP standard. It supports many phones and is available for free in a 5 user version.
Faxfrontend is a clean way to print to fax while using a desktop. It provides a GUI interface to print to fax using CUPS to Hylafax. When you print, a box pops up that lets you provide the fax number or find the number to use from the built in address book. It can also run as a standalone application to fax files or just a cover sheet.
AvantFAX allows users on any platform to view and send faxes without having to install special software. It also allows administrators to manage users, their permissions, fax lines, fax categories, etc. AvantFAX can be accessed from the local network and remotely via Internet using standard networking equipment.
GROUP-E is collaboration software which integrates groupware, project management, and business server on one platform. The solution is based on a LAMP architecture (Linux, Apache, MySQL, PHP). GROUP-E offers project management, transparent Samba (file server) integration, integration of Cyrus IMAP server with administration and personal SIEVE filters, support for SyncML 1.0, LDAP-based user management with single sign-on authentication, and LDAP contact databases. GROUP-E also provides ActiveSync for synchronization.
cupsfax is a set of two scripts to integrate a HylaFAX fax server into the CUPS printing system. To send a fax, the user prints it to the designated printer queue. He will then receive email with a link to a Web form. In this Web form, the user may enter additional parameters (most importantly the receiving fax number). This way, there are no additional conditions on what can be printed, like fax numbers embedded into the file or job name. This can also be fully integrated into a Wamba/CUPS configuration, enabling Windows clients to send arbitrary documents as faxes. It also gives the full power of the CUPS print processing pipeline to sending faxes, and makes it possible to specify additional faxing options.
Sipcat is a software IP telephony system that helps businesses increase productivity and reduce telecommunication costs. It allows you to start running your own voice over IP PBX in a matter of minutes. It contains a complete Linux distribution, including Asterisk and all required 3rd party software.