Berkeley DB (libdb) is a programmatic toolkit that provides embedded database support for both traditional and client/server applications. It includes b+tree, queue, extended linear hashing, fixed, and variable-length record access methods, transactions, locking, logging, shared memory caching, database recovery, and replication for highly available systems. DB supports C, C++, C#, Java, PHP, and Perl APIs. It supports key-value pair (NoSQL), SQL, and Java Object formatted data. It is available for a wide variety of Unix platforms as well as QNX, Android, Mac OS X, and several varieties of Windows.
ZMailer is an internet message transfer agent. It is intended for gateways or mail servers or other large site environments that have extreme demands on the abilities of the mailer. It was motivated by the problems of the Sendmail design in such situations. It is intended and designed as a multi-protocol mailer. The only protocol supported in this distribution is RFC822 (and variations).
Java Development Environment for Emacs (JDEE) is an Emacs-based integrated development environment (IDE) for developing Java applications and applets. Features include multiple code browsers, a JPDA-based debugger, method and field completion, template-based and procedure-based code generation, Java source code interpreter, context-sensitive help, and more.
PostgreSQL is a robust relational database system with over 25 years of active development that runs on all major operating systems. It is fully ACID compliant, and has full support for foreign keys, joins, views, triggers, and stored procedures (in multiple languages). It includes most SQL92 and SQL99 data types, including INTEGER, NUMERIC, BOOLEAN, CHAR, VARCHAR, DATE, INTERVAL, and TIMESTAMP. It also supports storage of binary large objects, including pictures, sounds, or video. It has native programming interfaces for C/C++, Java, .Net, Perl, Python, Ruby, Tcl, and ODBC, among others, and exceptional documentation.
XCmail is a MIME and multi POP3 capable mailtool for X11 using the Xclasses X11 layout library. Its main purpose is to read and write mail, allowing any kind of data to be attached. It can handle MIME types, has helpers to show different types, and can encode and decode binary data into ASCII to allow it to be transported as mail over the Internet. It has many built-in functions such as 2 vCards, unlimited POP3 servers, SMTP, SMTP after POP3, SMTP-AUTH (RFC2554), addressbook, encoders, filters, a special spam filter, spell checker, xface, and a new "virtual folder" concept. It also uses external programs to enhance its feature set. XCmail can be extended through a plugin interface.
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.
RealPlayer plays streaming audio and video over the Internet in real-time. It plays RealAudio, RealVideo, MP3, 3GPP Video, Flash, SMIL 2.0, JPEG, GIF, PNG, RealPix, RealText, Ogg Vorbis, and Ogg Theora. It is available for Windows, Macintosh, Pocket PC, Nokia 9200 Series, Nokia 7650, Palm OS 5-based handhelds, Linux, Solaris, and many Unix variants.
rsync is a replacement for rcp (and scp) that has many more features. It uses the "rsync algorithm" which provides a very fast method for remote files into sync. It does this by sending just the differences in the files across the link, without requiring that both sets of files are present at one of the ends of the link beforehand.