Backlinks module provides a wiki-style "what links here" filter for Views: give it a node id (via URL argument, for instance), and it will generate a list of all nodes linking to that node, courtesy of search module's index.
After enabling the module, two pre-configured views will be created for you: a "backlinks" view tab on each node page, and a backlinks block view, which generates a block with a list of backlinks on each node page (after you enable it at admin/build/block). With the Views UI module, you can configure these at admin/build/views; you may want to turn off the menu tab, add an RSS feed argument, change the view type, etc.
Note to users of Drupal 6 and later: Backlinks module has been incorporated into Views 2, and therefore the Drupal 5 branch of Backlinks will be the last. On Drupal 6 simply install the Views module and enable the backlinks view, or create your own using the "Search: Links to" argument.