title: What are some examples of Go interfaces?
body: <p>I found <a href="http://scienceblogs.com/goodmath/2009/11/11/googles-new-language-go/" rel="noreferrer">an interesting blog post</a> about Go.  </p>
  
  <p>I am trying to understand the concept of interfaces, but I find it very hard to do so from the code fragment in the blog post, and nearly impossible from <a href="http://golang.org/doc/go_spec.html" rel="noreferrer">the language specification</a>. </p>
  
  <p>Can anyone point out a simple example of Go's interfaces in a working program?</p>