How do I alter a boolean value and display a string in views output?
Well, that was a lot easier than I thought. Basically took a gander into node.views.inc and got the answer.

function MYMODULE_views_data_alter(&amp;$data) {
  $data['MYENTITY']['MYFIELD'] = array(
    'title' =&gt; t('MYFIELD'),
    'field' =&gt; array(
      'handler' =&gt; 'views_handler_field_boolean',
      'click sortable' =&gt; TRUE,
      'output formats' =&gt; array(
        'drunk-sober' =&gt; array(t('Drunk'), t('Sober')),
      ),
    ),
    'filter' =&gt; array(
      'handler' =&gt; 'views_handler_filter_boolean_operator',
      'label' =&gt; t('MYFIELD'),
      'type' =&gt; 'yes-no',
      'use equal' =&gt; TRUE,
    ),
    'sort' =&gt; array(
      'handler' =&gt; 'views_handler_sort',
    ),
  );
}