Update index.js

components/sections/comments/index.js

@@ -10,6 +10,15 @@ var style = {
 var sectionHTML = (
   <section id="comments" style={style}>
     <h2>Comments and questions</h2>
+
+    <p>If you enjoyed this book, or you simply found it useful for something you were trying to
+    get done, and you were wondering how to let me know you appreciated this book, you can always
+    <a class="link" href="https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=QPRDLNGDANJSW"
+    >buy me a coffee</a>, however much a coffee is where you live. This work has grown over the
+    years, from a small primer to a 70ish print-page-equivalent reader on the subject of Bézier
+    curves, and a lot of coffee went into the making of it. I don't regret a minute I spent
+on writing it, but I can always do with some more coffee to keep on writing!</p>
+    
     <div id="disqus_thread"/>
   </section>
 );