I don't think there is native (command-line) zipping in Windows, but on Mac, one can use the built-in commands: zip and unzip. For Windows, I'm using the 7-zip command-line utility, but there are others. If anybody has any other recommendations, I'm all ears... - thanks.
For Windows use the http://www.info-zip.org/ distribution of zip. Verify for yourself but I believe it has pretty flexible licencing. Mac uses this distribution as the basis of their command line zip functionality so it will help with cross platform compatibility as well.