tar and feather

vi.

[from Unix tar(1)] To create a transportable archive from a group of files by first sticking them together with tar(1) (the Tape ARchiver) and then compressing the result (see compress). The latter action is dubbed feathering partly for euphony and (if only for contrived effect) by analogy to what you do with an airplane propeller to decrease wind resistance, or with an oar to reduce water resistance; smaller files, after all, slip through comm links more easily. Compare the more common tarball. Earlier, the phrase referred to a punishment in which the victims had tar being poured upon them and then, whilst the tar was still sticky, having a pillow full of feathers - or other material — thrown at them. See http://www.nwta.com/Spy/spring99/tar.html.