Useful OSX-specific command line tools

Life-hacker has a short list of uses OS X command line programs that aren't just standard GNU/*nix commands: http://lifehacker.com/eight-terminal-utilities-every-os-x-command-line-user-s-1593793109

This mentions homebrew, which I hadn't heard of before. This answer to a stack overflow question about what are the differences between homebrew and macports gives some info (install location, user space vs sudo use, number of packages, support for multiple versions etc) but may not be enough to allow a definite decision on which to use without some experimentation. For science it appears currently homebrew has some but not all of the standard packages I'd expect.