Is there a reliable way to show Drupal messages from JavaScript?

I need to show status messages (the kind typically shown by drupal_set_message()) in my module’s JavaScript code. How can I do this reliably, such that the theme and placement of the messages remains consistent with the way drupal_set_message() does it?

I’m looking for a solution that accounts for the presence or absence of prior messages on the page, and that works for any theme.

Pointing to existing modules that perform this would be great!