coNCePTuaL is available freely under a BSD-style license. (The primary difference from the stock BSD license is that modified versions of the code must indicate that they are modifications.) The source code—and a few binary distributions, as well—can can be downloaded from the coNCePTuaL project page on SourceForge.net:

The software is currently provided as a source tarball, a source or binary RPM, or a binary Debian package.