Abigail is right. I use __DATA__ if I can get away with
it and it won't make my life difficult later. Most of
the times I can't since the scripts I write tend to be
installed and reinstalled on different machines requiring
different configurations, and I
don't want to edit the script each time I install. You
may even be able to use both methods at the same time
in some cases
(i.e. use a config file if it exists, or use __DATA__
if it doesn't).