capircvd is a voice/fax gateway. It receives fax (G3) and voice-calls using an ISDN-Bus, an AVM ISDN-Card (active or passive) and CAPI20 from isdn4linux, or AVM. It can be used on either P2P (with DDI) or P2M S0-bus. After reception, it can process files (send as mail) using an external handler (included).
The mgetty package contains an intelligent getty for allowing logins over a serial line (such as through a modem) and receiving incoming faxes. The companion program sendfax is used for sending faxes from the commandline or from other applications. The third main component is vgetty/vm which can be used with a voice-capable modem to implement an answering machine, a voice menu system, and similar things.
SffTools consists of SffToBmp, a little utility that converts Structured Fax Files to BMP, PBM, JPEG, or single- and multipage TIFF format, and SffView, a GUI viewer for those files. The tools should be especially useful to people who are faxing with ISDN cards because the CAPI interface of these cards generates such files. CAPI support for Linux is available for the active card AVM B1 and the passive card AVM Fritz!.
fax4CUPS is a very simple shell script that acts as a CUPS backend for a serial fax modem. Essentially, you print with lpr and the fax is sent. The nice thing is that you have CUPS around, and this means, for instance, that you can check whether your fax has been sent just using your favorite browser (as you would do for any other printer), even if the fax modem is really on a remote server. It supports efax, HylaFAX, mgetty-fax, and Capisuite.
TkScanFax is a TCL/Tk GUI fax program in ANSI C/POSIX with support for efax and multiple languages. It helps make the cover page, convert text files, PostScript files, and image files into fax files, and send faxes. It also uses scanners by using backends such as SANE. The efax program supports Class-1 faxmodems.
YaaCs (Yet Another Advanced Cati system) is written in Tcl/Tk to manage and realize computer assisted telephone interviewing (CATI) and telemarketing. It make easy monitoring survey progress (giving several information), and it allows the management of the the survey with several administration tools. It simplifies the interviewer's work reading all contact's data from an easy and functional GUI. It can send faxes via hylaFAX and save all contact's data in a PostgreSQL database.