The question I'd ask your potential attendees, is why are they interested in Perl? What does it bring to the table that they don't have in their other languages? How can knowing Perl help them?

If you can give them a reason to do perl, and some basic resources, the rest will take care of itself.

I've listed a few things below that I think are cool bits of perliana.

PAR::Packer is worth mentioning, it solves the problem of "how do I distribute my work?".

I'd but things like strict, warnings, diagnostics, Perl::Tidy, Perl::Critic, under a "Perl Hygiene" header. Also PBP needs mention here. It's worth noting that while Perl gives you the technical freedom to hang yourself, we use cultural mores to restrict our behavior, rather than technical limitations. PBP does a good job of covering a lot of these rules and practices that have developed. A little basic hygiene goes a long way.

Test::* also deserves mention.

Inline::C and friends are also good to point out. As a C programmer, Inline::C and the Test modules are enough to get excited about.