Expand­ing on an idea orig­i­nally posted on the Freako­nom­ics blog, Andrew Lynch sug­gests solic­it­ing peo­ple you admire or respect for an unpaid intern­ship:

Find some­one you really admire or respect. Email them. Describe your skills, how you can help them, what you have to offer. Link them to your blog full of qual­ity posts. Then offer to work for them for free. If they accept, take what­ever task they give you and knock it out of the park. Go the extra mile. Make it your most impor­tant task for the day, or week, or month. Do the work quickly and effi­ciently. Then, when you’re done, email the per­son and say that it was a plea­sure work­ing for them, and you’d love to help them out in the future if they have any other cool projects lined up.

Pretty good advice for both stu­dents and those seek­ing a grad­ual career change.