#contextual filter

[acmeinternet-blog]

Filtering Drupal Views content by node id

In four easy steps:

Add a Contextual Filter (or "Argument", depending on your version of Drupal).

Select "Content: Nid" (or "Node: NID").

Under "When the filter value is NOT available" (or "Action to take if argument is not present:") select "Provide default value" (or "Provide default argument").

From the "Type" dropdown menu, select "Content ID from URL" (or "Node ID from URL").

Via this stackoverflow post.