One of my best friends came to me, asking to write a quick script. The company he helps run gets thousands of single column CSV files from some automated process. Every month, they need to run a "report" of these files, essentially concatentating them together and delimiting the output with 3 lines of 9 'x's. This process was being done across thousands of files, all manually. He knew there was a better way so he came to me to cut some man hours off of their load.

When I first saw the problem, I thought, that has to be like 5 lines of python. Here is what I came up with:
import glob

with open("../output.csv", 'w') as output:
    for csv in glob.glob("*.csv"):
        with open(csv, 'r') as infile:
            data = infile.read()
        output.write(data)
        output.write("xxxxxxxxx\nxxxxxxxxx\nxxxxxxxxx\n")

Pretty close for a first pass. But then I realized the company is exclusively windows machines, and windows doesnt have python installed by default like mac or linux. So I took a second pass at it using window's batch:
set out=../output.csv
type nul > %out%
for %%f in (*.csv) do (
    type %%~nf.csv >> %out%
   @echo xxxxxxxxx >> %out%
   @echo xxxxxxxxx >> %out%
   @echo xxxxxxxxx >> %out%
)

This was a rather harsh reminder of why I love unix and python