Try doing the things you can do easily in Perl. Try doing the things that are harder in Perl. Try getting into the mindset of that language so you can see problems from different points of view.
Which begs the questions, "What is the mindset of language X?" and "What is language X good at that Perl isn't?" I know that some of the answers are rather obvious (C is good for system-level work, Java is not too bad for programs which need to run in many different environments, and Lisp is good for writing editors :), but what about the areas which don't scream "Use X to write me!" Where do the newbies (me included) go to discover the mindset of Ruby and how it differs from Perl? How do we get perspective on languages?