I quite like it, and have almost a singalong bit for the meaning attached to each character I add to a long tar command

tar - [create] [verbosely] [a g/bzip'd compressed] [file named] foo.tgz (from) input_dir

tar -cvzf foo.tgz input_dir

Your version doesn't seem as 'fun', I guess zcat and PIPE are just hard to rhyme along to.