diff --git a/README.md b/README.md
index 92a7c21..e559534 100644
--- a/README.md
+++ b/README.md
@@ -5,9 +5,11 @@ FastTracker 2 .XM player, written for fun.
 [Demo](http://www.a1k0n.net/code/jsxm/) [warning: plays sound immediately on
 load]
 
-It only plays one .XM: "my dirty old kamel" by Alexander Bulér aka
+By default it plays "my dirty old kamel" by Alexander Bulér aka
 [Zalza](http://zalza.bandcamp.com/). I love this tune, and wrote this code just
-to play it.
+to play it. It can also load other .XMs by loading index.html?_tune-uri.xm_,
+though it either needs to be local to your domain or cross-origin resource
+sharing must be enabled for that to work.
 
 It is fairly feature-complete, but is missing a bunch of effects.