diff --git a/bash/tag.sh b/bash/tag.sh
new file mode 100755
index 0000000..8ab3845
--- /dev/null
+++ b/bash/tag.sh
@@ -0,0 +1,2 @@
+# just list the files so we can pipe it.
+grep -l "\+ $@" *md
diff --git a/bash/um b/bash/um
index d0616c1..33801fd 100755
--- a/bash/um
+++ b/bash/um
@@ -18,8 +18,10 @@ case "$1" in
     rename)
         $UMBASEPATH/rename.sh "${@:2}"
         ;;
+    tag)
+        $UMBASEPATH/tag.sh "${@:2}"
+        ;;
     *)
-        # else
-        echo "usage: um (next|last|cat|rename)"
+        echo "usage: um (next|last|cat|rename|tag)"
         ;;
 esac