I agree that dates should be in a sortable format.

For filenames, I often use something like YYYYMMDD_HHMMSS-filename. It varies because sometimes I only need the date; sometimes I don't need seconds; etc.

It doesn't much matter one way or the other, but I do think that, if human readablity is a goal, different separation characters for date components and time components are helpful. So, how about ISO 8601? YYYY-MM-DDTHH:MM:SS. Several CPAN modules already handle it...

-sauoq
"My two cents aren't worth a dime.";