What is CCP4?
CCP4 is a crystallographic program system, and can be downloaded from . It is free for academic use; the license is at . Documentation is at , and a mailing list (CCP4BB) is at . The mailing list archive at http://proteincrystallography.org/ccp4bb/ seems to be more up-to-date than the official one.
Installing CCP4's distributed precompiled binaries
As a courtesy, CCP4 compiles binaries for most major platforms so that you don't have to.
Visit the ccp4 download page for detailed instructions.
Installing from sourcecode
Many people prefer to compile the programs from the distributed source code, which can be obtained from the ccp4 download site. The configure script should permit you to do this on any modern unix or linux platform.
Various users have made unofficial (and unsupported) install options available as a courtesy to their colleagues for some platforms. The following will hopefully grow into a comprehensive listing of links that describe such options. Even if you don't use these install options, visiting the links relevant to your platform might be worth your time.