diff --git commands/core/interactive.drush.inc commands/core/interactive.drush.inc
new file mode 100644
index 0000000..252819e
--- /dev/null
+++ commands/core/interactive.drush.inc
@@ -0,0 +1,67 @@
+<?php
+// $Id$
+
+/**
+ * Implementation of hook_drush_command().
+ *
+ * In this hook, you specify which commands your
+ * drush module makes available, what it does and
+ * description.
+ *
+ * Notice how this structure closely resembles how
+ * you define menu hooks.
+ *
+ * @return
+ *   An associative array describing your command(s).
+ */
+function interactive_drush_command() {
+  $items['interactive-shell'] = array(
+    'description' => 'Start an interactive phpshell with a bootstrapped Drupal environment',
+    'aliases' => array('ish'),
+  );
+  return $items;
+}
+
+
+function drush_interactive_shell() {
+  if (drush_shell_exec("which phpsh")) {
+    $drushinc = DRUSH_BASE_PATH . '/drush.php';
+    $phpshrc = <<<EOD
+<?php
+\$drush_interactive_shell = TRUE;
+error_reporting(E_ALL);
+
+switch (\$___phpsh___codebase_mode) {
+case '':
+  // Put default library includes here.
+  //require_once 'relative-path-from-repo-head/lib/codebase_include.php';
+  require_once '$drushinc';
+  break;
+
+case 'none':
+  // Vanilla php
+  break;
+
+// Put any custom codebase modes here, e.g.:
+//case 'core':
+//  // Would only load 'core' library includes here, perhaps for faster startup
+//  // in a very large codebase.
+
+default:
+  fwrite(STDERR, 'Unknown codebase mode '.\$___phpsh___codebase_mode."\n");
+  break;
+}
+drush_main();
+EOD;
+    $path = $_SERVER['HOME'] . '/.phpsh/rc.php';
+    if (is_writable(dirname($path))) {
+      file_put_contents($path, $phpshrc);
+    }
+    else {
+      // @todo Unwritable.
+    }
+
+    drush_shell_exec_interactive('phpsh');
+  }
+}
+
diff --git drush.php drush.php
index c082ded..ed58525 100755
--- drush.php
+++ drush.php
@@ -44,7 +44,7 @@ drush_set_context('argv', $GLOBALS['argv']);
 set_error_handler('drush_error_handler');
 register_shutdown_function('drush_shutdown');
 
-exit(drush_main());
+if ($drush_interactive_shell !== TRUE) exit(drush_main());
 
 /**
  * Verify that we are running PHP through the command line interface.