I'd just make a list of some of the projects you've worked on -- it helps if you can point to them, saying something like "I've submitted Hash::Browner and Array::OfHope to CPAN, patched Slash which runs these websites, and hooked up a database running on the Mars probe to a web server on this Palm Pilot right here."

That depends on your experience, though -- if your examples are all hidden away under NDA somewhere, then ask for a technical interview. Couldn't hurt.

(There's no reason not to mention Perl Monks.)