PerlySense collects together a suite of tools to make working with Perl easy and powerful. Two major Perl tools that will keep your code looking great, Perl::Tidy and Perl::Critic, are seamlessly integrated to show you code issues while you type (or when you save - depends on your preference settings. Quick navigation tools allow you to jump from where subroutines and modules are called, to where they are defined. There's also a regex creation tool, and a whole lot more that I have yet to explore.
PerlySense is very cool. If you're an emacs user you'll need to manually move the perly-sense.el file it provides into the appropriate location, but that's a minor nit in a development release. The underlying idea is excellent, and the seemless interaction with my editor of choice makes the whole package very fun to play with.