If using a regexp...:

if( $string =~ m![/\\]([^/\\]+)$! ) {
    print $1, "\n";
}
[download]

This works as long as you're dealing only with paths where there isn't a trailing filename. And of course it would run amok if the path didn't start with either a / or a \, or if a directory name allowed embedded / or \ characters. :) caviet lector.