From the LWN FAQ:
> What are subscriber links
>A subscriber link is a mechanism by which LWN subscribers may grant free access to specific LWN articles to others. It takes the form of a special link which bypasses the subscription gate for that article.
> Where is it appropriate to post a subscriber link?
> Almost anywhere. Private mail, messages to project mailing lists, and blog entries are all appropriate. As long as people do not use subscriber links as a way to defeat our attempts to gain subscribers, we are happy to see them shared.