Of course Perl is cool because it is powerful. It lets you focus on the important part of a program, the algorithms, instead of spending time making sure that you don't mess-up you pointer arithmetic or your buffer handling or creating classes for every darn structure you need.

But I think that above all Perl is cool because it is complex. I like learning new idioms in Perl just as much as I like learning new idiomatic expressions in English. It keeps me interested in the language itself.

It took me 2 years to feel confident enough to use map in production code, I still haven't used pack much... there is just so much in the language, without even getting into Wizard territory, that I feel I can keep learning for a good number of years.

Which is what I like! Learning and feeling that I am improving with time.

And when I get bored I know there will still be undocumented features, glob mongering and the likes to keep me busy for ever...