Plugin hook within a plugin.

[JWH_Matthew]

Would it be possible to add hooks to a plugin for say?

Example:
I created a recent activity plugin, I would like it to display all recent activity. Would it be possible for me to add this code and allow others to insert recent activities into my list?

Code:

<ul>
  <li>example activity</li>
  <?php exec_action(simple-recentactivity); ?>
</ul>

does this make sense?