On OSX at least, if you run it as CAL instead of cal you get a sideways calendar:<p><pre><code>    mcphage:~ $ CAL
        May 2016
    Mo     2  9 16 23 30
    Tu     3 10 17 24 31
    We     4 11 18 25
    Th     5 12 19 26
    Fr     6 13 20 27
    Sa     7 14 21 28
    Su  1  8 15 22 29</code></pre>