I find myself using File::Find more and more now that I've got the hang of it. Typically you set up like so:

use File::Find;
find( \&do_stuff, $from_dir );
[download]

and do_work() is the place where all the real work gets done.

A couple caveats that I've found (the hard way...) about what you can do inside do_work():

• Don't change $_ inside do_work(). If you want to, save a copy on entry and change it back before returning.
• As Corion mentions, the working directory is changed to each recursed directory under your starting point. If you change directories inside do_work(), save a copy of the current directory on entry and chdir back to it before returning.
• The usual file test operator caveats apply, for example -f $File::Find::name and -l $File::Find::name are both true if the file is a symlink to another file. If you're interested in symbolic links, test for those first, before you test for file- or directory-ness.