This keeps popping up from time to time at work, because I get input files created by someone else in Windows and I work with them in *NIX environments.
The DOS-format normally doesn’t bother me until sed/awk/grep/cut scripts break when unexpected characters appear. Editing in vim and replacing them with
"%s/^M//g" normally works, but I found an elegant solution here:
How to convert DOS to Unix (and vice-versa, if ever!)