diff --git a/mbox2web b/mbox2web
index a56593a..414c40a 100755
--- a/mbox2web
+++ b/mbox2web
@@ -231,6 +231,13 @@ def render_body(msg):
         }
         bodyhtml = bodytmpl.render(context)
 
+    elif content_type == "application/pgp-signature":
+        # A PGP signature outside of a multipart/signed - useless
+        bodytmpl = jenv.get_template("body_application_pgp-signature.html")
+        context = {
+        }
+        bodyhtml = bodytmpl.render(context)
+
     else:
         raise RuntimeError("Content-type " + content_type + " not implemented yet")
 
@@ -239,6 +246,7 @@ def render_body(msg):
 
 def archive(msg):
     mid = get_message_id(msg)
+    print("M", mid, file=sys.stderr)
     encmid = encode_message_id(mid)
     msgdir = basedir + "/msg/" + encmid
     os.makedirs(msgdir, exist_ok=True)
diff --git a/templates/body_application_pgp-signature.html b/templates/body_application_pgp-signature.html
new file mode 100644
index 0000000..c284ede
--- /dev/null
+++ b/templates/body_application_pgp-signature.html
@@ -0,0 +1,8 @@
+<div class="partouter">
+    <div class="partheader">
+       application/pgp-signature
+    </div>
+    <div class="partinner">
+        (free floating signature - a blank cheque?)
+    </div>
+</div>