A few days ago I needed to change the line endings of a text file on a Mac. This Mac did not have Textmate (of course).
I guess every unix system has vi:
:set fileformat=unix :w
that simple :P
btw. This fix, depends on a fileformats setting (available on mosts systems). When there's no fileformat setting the following command can be given:
:%s/<ctrl>-v<enter>//