This adds plain text format support.

diff -Nurp ../email.orig/email.module ./email.module
--- ../email.orig/email.module	2010-10-18 12:54:22.000000000 -0500
+++ ./email.module	2010-10-18 12:54:28.000000000 -0500
@@ -20,6 +20,9 @@ function email_theme() {
     'email_formatter_contact' => array(
       'arguments' => array('element' => NULL),
     ),
+    'email_formatter_plain' => array(
+      'arguments' => array('element' => NULL),
+    ),
   );
 }
 
@@ -99,6 +102,11 @@ function email_field_formatter_info() {
       'field types' => array('email'),
       'multiple values' => CONTENT_HANDLE_CORE,
     ),
+    'plain' => array(
+      'label' => t('Plain Text'),
+      'field types' => array('email'),
+      'multiple values' => CONTENT_HANDLE_CORE,
+    ),
   );
   if (module_exists('spamspan')) {
     $formats += array(
@@ -141,6 +149,13 @@ function theme_email_formatter_contact($
   return !empty($element['#item']['safe']) ? l(t('Email contact form'), 'email/'. $element['#node']->nid .'/'. $element['#field_name']) : '';
 }
 
+/**
+ * Theme function for 'plain' email field formatter.
+ */
+function theme_email_formatter_plain($element) {
+  return !empty($element['#item']['safe']) ? $element['#item']['safe'] : '';
+}
+
 
 /**
  * Implementation of hook_widget_info().