C-Kermit is a combined serial and network communication software package offering a consistent, medium-independent, cross-platform approach to connection establishment, terminal sessions, file transfer, character-set translation, numeric and alphanumeric paging, and automation of communication tasks. Recent versions include FTP and HTTP clients as well as an SSH interface, all of which can be scripted and aware of character-sets. It supports built-in security methods, including Kerberos IV, Kerberos V, SSL/TLS, and SRP, FTP protocol features such as MLSD, and source-code parity with Kermit 95 2.1 for Windows and OS/2.
Calc is arbitrary precision arithmetic system that uses a C-like language. It's useful as a calculator, an algorithm prototype, and as a mathematical research tool. More importantly, calc provides a machine-independent means of computation. Calc comes with a rich set of builtin mathematical and programmatic functions.
Star is a very fast, POSIX-compliant tar archiver, maintained for more than 30 years. It saves many files together into a single tape or disk archive, and can restore individual files from the archive. It includes command line interfaces for the "tar", "Sun-Tar", "cpio", "pax", and "gnutar" command-line syntax. It includes a FIFO for speed, a pattern matcher, multi-volume support, the ability to archive sparse files and ACLs, the ability to archive extended file flags, automatic archive format detection, automatic byte order recognition, automatic archive compression/decompression, remote archives, and special features that allow star to be used for full and incremental backups. It includes the only known platform independent "rmt" server program.
TAO (The ACE ORB) is an advanced, CORBA-compliant, real-time Object Request Broker (ORB). It is designed to meet the stringent Quality of Service (QoS) requirements of real-time applications, resulting in superior end-to-end predictability, efficiency, and scalable performance. It implements the latest CORBA specifications from the OMG. It is built with components from the ADAPTIVE Communication Environment (ACE) C++ framework, resulting in a highly extensible architecture, adaptability to a wide variety of situations, and portability across a broad range of platforms. Although TAO was designed to meet the demanding requirements of real-time applications, it is also well-suited for general-purpose CORBA applications.
Hoard is a scalable memory allocator (malloc replacement) for multithreaded applications. Hoard can dramatically improve your application's performance on multicore machines. No changes to your source are necessary; just link it in. Hoard scales linearly up to at least 64 processors. Supported platforms include Linux, Solaris, Mac OS X, and Windows.
Gforth is a fast and portable implementation of the ANS Forth language. It works nicely with the Emacs editor, offers some nice features such as input completion and history and a powerful locals facility, and it even has (the beginnings of) a manual. Gforth employs traditional implementation techniques: its inner innerpreter is indirect or direct threaded. Gforth runs under Unix, Win95, OS/2, and DOS and should not be hard to port to other systems supported by GCC.