A lot of companies are listed already by others, so I'll point to "some" applications. Of course, the best way to find out is using freshmeat and browse by category Perl :)

That will list a massive ammount of applications written in Perl, but to make life a little easier, I'll list a few that come to mind:

--
b10m

In reply to Re: Well known application that use Perl by b10m
in thread Well known application that use Perl by lergot

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