Xray

The Difficulty of Identifying All Hook Implementations

explained by Matej Midriak (wapnik):

Sorry i don't have time now to examine the code to find all those
patterns (if that's even possible without reading the entire drupal
sources), but here is one example.
In drupal_mail() function:

Finding a module
drupal node info block
site:drupal.org node information block module
http://drupal.org/project/about_this_node

if not displayed

creation date and time

creation author (user who created the node)

And also:

promoted to front page status

sticky status

node ID (NID)

published status

commenting status (enabled, read only, or disabled)

should theoretically be visible

Asked in IRC #drupal

has anyone made a Drupal 7 module for seeing the system names for all permissions? (now the Permissions UI uses human-friendly names and descriptions)

No response.

Update: This has been incorporated into Xray.

Visualize plugin will be great for graphs (like what percentage of nodes on a site are each node type)