A tiny stand alone (g)awk script to count word frequncies. It lowercases input, removes punctuation, and tallies the count of each value. (An easy to use stand-alone awk script, instead of having to load a function library from gawk itself.)
$chmod +x freq
$cp freq /usr/local/bin
(or somewhere in the your PATH)
$< ./createdb.ddl | freq | sort -rn -k2 | head -n 3
commit 2884
date 2096
tablespace 2094
$curl -s "http://www.gutenberg.org/files/100/100-0.txt" | freq | sort -rn -k2 | head
the 30002
and 28358
i 21867
to 20816
of 18815
a 15992
you 14437
my 13191
in 12032
that 11781