I think that nowadays Perl is NOT ENOUGH... And it is a sorrowful fact. You must know a bunch of other programming languages, if you want a real good job. The IT people thinks that Perl is only good for system administrators to create background processes for their own crypted needs. Of course it 's not true, but if you want to develop interesting and robust projects you have to know Java, etc.
On the other hand I feel sometimes, that would be nice to know other professions, not just computers. For example i would learn architecture, just to become a good architect who can write useful Perl scripts :-)

You see as lot of the world as you know it...

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tune