I actually subscribe the annals.org , nejm.org , in e-mail for free, and I get JAMA in the mail from being an AMA member. Once you get the e-mails with the new topics being discussed, you can just go to their website and read the abstract. If you are interested in learning more about an article after reading the abstract, you can go to your local med school library to copy the whole article. Not a perfect set up, but at least it's very cheap.