Reconfiguring Ctrl on a MacBook Pro's keyboard to another key
Install KeyRemap4MacBook, save a file like this as ~/Library/Application Support/KeyRemap4MacBook/private.xml:

&lt;?xml version="1.0"?&gt;
&lt;root&gt;
  &lt;item&gt;
    &lt;name&gt;test&lt;/name&gt;
    &lt;identifier&gt;test&lt;/identifier&gt;
    &lt;autogen&gt;__KeyToKey__ KeyCode::OPTION_R, KeyCode::CONTROL_R&lt;/autogen&gt;
  &lt;/item&gt;
&lt;/root&gt;


Then open the KeyRemap4MacBook application, press the ReloadXML button, and enable the setting.