title: rails 3, heroku, how to use sessions
body: <p>I saw a great answer re how to setup sessions for rails 3 
  ( <a href="https://stackoverflow.com/questions/2588241/rails-sessions-current-practices-especially-for-rails-3">Rails sessions current practices</a> )</p>
  
  <p>we gather a series of questions from the user and I'd like to maintain in session a list of their answers until we get to the end then write it all out...</p>
  
  <p>but am not sure how to write and read info from the session... any quick pointer would be appreciated on how to save, for example, the contents of a hash</p>
  
  <p>Also, does having our app hosted on a grid at Heroku change how we could/should handle sessions?</p>
  
  <p>Cheers,
  JP</p>