One thing I still like about Perl is how well the regex syntax is integrated into the language, combined with being installed in just about every Linux modern Linux system, makes it really accessible from your fingertips.

If you're in a hurry and just need to do some one-off slicing and dicing, there's not much more powerful than being able to say, eg:

  $data = "foobarfoo";
  $data =~ s/bar/baz/g;
  print "$data\n";

versus python's more dramatic and formal:

  import re
  data = "foobarfoo"
  data = re.sub('bar', 'baz', data)
  print data

For some reason, the Perl =~ notation sticks in my head much more easily than the Python method.

Of course you can string a bunch of sed commands together in a shell script as well, but I find that becomes unwieldy pretty quickly in a lot of situations.