Every now and then you come across something and say, "Gee, that might come in handy someday, but I have no idea for what." This might happen to you when you're browsing at a flea market or garage sale; or if you're like us, it might happen when you're browsing through public domain software.
Now let's compare combinations of rot and:
rot rotates the text 90 degrees. tail -r turns the text "upside down" (last line in becomes the first line out, and so forth).
rot can also rotate the output ofto print down a page instead of across. By now, we hope you have an idea of what rot can do!