Token Content Access

Token Content Access allows you to restrict access to individual nodes using URL tokens. In order to view protected nodes, users must provide a unique token via the URL. This allows nodes to be published and viewable to anonymous users (for instance with a special link from an email campaign) but not visible to the public at large. It also automatically hides any TCA-protected content from Views results.

This module is designed with performance in mind, so it doesn't use traditional solutions like node grants. This also means that it's not guaranteed to block access in all situations, for instance if you expose node content via means other than Views.

Original development by Grant Gaudet (bonus).