diff --git a/src/sugar/activity/activity.py b/src/sugar/activity/activity.py
index f34553d..e3a5cc3 100644
--- a/src/sugar/activity/activity.py
+++ b/src/sugar/activity/activity.py
@@ -724,19 +724,12 @@ class Activity(Window, gtk.Container):
         pixbuf = pixbuf.scale_simple(style.zoom(300), style.zoom(225),
                                      gtk.gdk.INTERP_BILINEAR)
 
-        # TODO: Find a way of taking a png out of the pixbuf without saving
-        # to a temp file. Impementing gtk.gdk.Pixbuf.save_to_buffer in pygtk
-        # would solve this.
-        fd, file_path = tempfile.mkstemp('.png')
-        os.close(fd)
-
-        pixbuf.save(file_path, 'png')
-        f = open(file_path)
-        try:
-            preview_data = f.read()
-        finally:
-            f.close()
-            os.remove(file_path)
+        preview_data = []
+        def save_func(buf, data):
+            data.append(buf)
+
+        pixbuf.save_to_callback(save_func, 'png', user_data=preview_data)
+        preview_data = ''.join(preview_data)
 
         self._preview.clear()