title: express command not found in bash after installing it with npm
body: <p>just installed new ubuntu vm to test around with node
  installed things in this order:</p>
  
  <pre><code>node
  mongodb-server
  npm
  express
  mongoose
  </code></pre>
  
  <p>now, trying to create a new app i noticed express cannot be used in the shell.
  <code>express -v</code>  returns
  express: command not found</p>
  
  <p>i installed npm like this</p>
  
  <pre><code>curl http://npmjs.org/install.sh | sudo sh
  </code></pre>
  
  <p>and i installed express this way</p>
  
  <pre><code>npm install express
  </code></pre>
  
  <p>any ideas?</p>