Different <title> per action, when using layouts?

I think you can simply use

<title><%= controller.action_name %></title>

or <title><%= controller.controller_name %></title>

etc.

If you want per-controller optional overrides, try:

<title><%= @title || controller.controller_name %>

Then just define @title for the controllers that you want to have the
layout use something other than the controller name.