title: Ubuntu 11.04: `apt-get install rake` -> "E: Unable to locate package rake"
body: <p>This is probably a type of "is it plugged in?" question, but after getting a default Rackspace image of Ubuntu 11.04 up. Running command (as root)</p>
  
  <p><code>apt-get install rake</code></p>
  
  <p>Fails with error</p>
  
  <pre><code>Reading package lists... Done
  Building dependency tree
  Reading state information... Done
  E: Unable to locate package rake
  </code></pre>
  
  <p>I'm missing something simple I'm sure.</p>