How to determine word frequency in a directory of files

Here is a fun one-liner for finding the most-used words in a directory based on file type:

$ find . -name "*.js" | xargs cat | tr -s '[:space:]:#()[]{}\"' '\n' | sort | uniq -c | sort -n

The output will resemble the following, in this example based on the United States Constitution:

$ find . -name "constitution.txt" | xargs cat | tr -s '[:space:]:#()[]{}\"' '\n' | sort | uniq -c | sort -n
(truncated)
 296 to
 308 shall
 314 and
 564 of
 796 the

The results can be lengthy, so it maybe be useful to page the output by appending | less to the end of the chain.