Call me old-fashioned, but I’ve been talking up the merits of writing letters to the press. The skills involved – tuning in to the issues, finding an angle, keeping it brief, and submitting it to the right person, in the right format at the right time – are many of those required in media relations.
Even better, you don’t need to find a client to try it out. Can I praise one student? Though writing in her fourth language (yes, fourth!), she has written letters on a range of subjects to student and national newspapers, lifestyle magazines and an international publication. Many were published. Her persistence alone will recommend her to employers.
PR Studies 
Excellent advice Richard. Letters to the media are a much under used PR tool. We use it all the time for clients, and should do it more for our own purposes. I’m amazed that more PR companies don’t use the technique.
And you’re right potential employers will be impressed by a student who has taken advantage of the opportunities. It’s not a new idea either. Back in ’89 when I was looking for my first PR job I had letters in a whole range of regional papers, national papers and PR Week commenting on PR related topics. I included cuttings with speculative application letters to PR companies. It worked a treat then and I suspect would be just as good today.