Why does it cost $20,000 a year to subscribe to a science journal?

If you've ever wanted to read more about a science article here on io9, and clicked through to the original journal article to read more, chances are you've been met by a subscription page (like the one up top) that asks you to either log in or fork over a grip of cash to read the article in full. » 9/21/11 6:20am 9/21/11 6:20am