CMVision is a real-time color classification and segmentation library which can track up to 256 colors in a 640x480 30fps video stream. The vision system core is a C++ library which is easily extensible for custom applications, and should compile on any *nix compatible environment. Also provided is a video capture library for Video4Linux II.
CMUbik is a library for mantaining a syncronized Berkeley database over multiple hosts. It has good failure semantics and strong authentication provided by the Cyrus SASL library. Its API is very similar to that of Berkeley DB, allowing existing applications to use it very easily.
CMUCL is a free, high performance implementation of the Common Lisp programming language which runs on most major Unix platforms. It mainly conforms to the ANSI Common Lisp standard. CMUCL provides a sophisticated native code compiler; a powerful foreign function interface; an implementation of CLOS; the Common Lisp Object System; which includes multimethods and a metaobject protocol; a source-level debugger and code profiler; and an Emacs-like editor implemented in Common Lisp. CMUCL is maintained by a team of volunteers collaborating over the Internet, and is mostly in the public domain.
CMC is a Perl/GTK+ mail client designed to be easy to use and fill the needs for features that are not present in other mailers, including HTML mail, multiple accounts, support for external viewers, compatibility with other mail clients, easy extendability, multiple mailboxes, etc.