How do we DELETE this new Rails 2.0 "Cookie Store"?

In the past, I would run this code to clear my session and cookie variables;

  def clear_session     session[:user_id] = nil     cookies[:user_id] = nil     cookies[:password_hash] = nil   end

I would then go into my \Docs & Settings\user_name\cookies and clear out the cookie file. Now, in Rails 2.0 (using the new SECRET key) I can't seem to LOCATE? what file this is being stored in so I can; 1. Clear it out (in code) 2. Delete it manually I expect this is a common question. Thank you, Kathleen