The last time I wrote code every day as part of my job, it was in Perl as part of some site development using the Mason framework.

I am unapologetic about my love for Perl. Something I learned in that role was how much more important transparency is than cleverness. Perl has a way of enticing you to do very "clever" things -- there's more than one way to do it, as the saying goes, and some of those ways are VERY NEAT! Unfortunately, a large number of the "neat" approaches also approach brainfuck-levels of oddness.

Most languages don't have that rabbithole, or at least the hole isn't that deep. But with perl, man, you can do some ridiculous and awesome things that even YOU won't immediately understand six months from now.

About the 2nd or 3rd time you get bit by that particular snake, though, you start to build your code much more conservatively, and with much more of a long-term intentionality built in. The code I wrote in that job after those lessons took root is still probably the best work I've done as a programmer -- neat, clean, consistent, and above-all understandable to whomever ended up needing to work on it later. And I put a lot of that down to just how easy it is to write HORRIBLE Perl.